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Disorders of Arteries and Veins

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					Section 5: Disorders of Skin Components

Chapter 28: Disorders of Arteries and Veins

Arterial disorders                                   determinates the life expectancy of the patient,
Atherosclerosis                                      although antiplatelet agents, lipid-lowering
      Atherosclerosis is a patchy accumulation       agents and bypass surgery may improve the
of lipid, mostly cholesterol, within the intima      prognosis as well as the symptoms of
of the vessel wall. Such plaques eventually          ischaemia.
                                                           Treatment options for atherosclerosis
ulcerate through the endothelial lining,
                                                     differ for claudication, rest pain or gangrene,
presenting a highly thrombotic surface.
                                                     and acute limb ischaemia. Treatment of
Platelets adhere to the ulcerated plaque and
                                                     intermittent claudication is conservative.
aggregates (platelet thrombi) may embolize
                                                     Patient is advised to stop smoking, walk
distally, or may initiate local thrombosis.
                                                     through the pain to stimulate development of
Inadequate collaterals, or rapid occlusion by
                                                     collateral circulation, do exercise programmes,
thrombosis or embolism, will lead to tissue
                                                     and avoid β-blockers and other risk factors.
infarction     (e.g.    peripheral      gangrene).
                                                     Vasodilators are of little benefit. Stenotic
Atherosclerosis is responsible for more than
                                                     lesions confirmed by arteriography can be
90% of arterial disease. It affects 5% of men
                                                     treated by balloon catheters. Once rest pain or
over the age of 50 years, of which 10% may           early gangrene have developed the situation
develop limb ischaemia; this increases to 20%        changes, for this state if left untreated,
if diabetic patients are included.                   amputation with be necessary to relieve pain
      Patients      present     initially     with   and preserve life. Treatment is with chemical
claudication (cramping pain on walking,              sympathectomy using prostacycline or its
experienced in calf muscles which is relieved        analogue iloprost if surgical bypass cannot be
by rest). The presence of persistent pain in the     constructed. In patients with acute limb
foot at night indicates the onset of ischaemia,      ischaemia urgent catheter angiography is done
which will lead to gangrene or ulceration if         to do infusion of a tissue plasmin activator
left    untreated.     Atherosclerosis     is    a   into the thrombus or emboli via the catheter,
physiological response to ageing. Thickening         unless to state of the limb demands
of the arterial wall, with an increase in            revascularization or amputation. Amputation
collagen and calcium deposition, causes loss         remains the final option in all types of
of elasticity and increased tortuosity of the        ischaemic disease of the lower limbs where
vessels in the elderly. Similar changes are seen     revascularization is impossible or ineffective.
in the vessels of younger patients with
hypertension.                                        Painful vascular disorders of the
                                                     extremities
      Risk factors for atherosclerosis include
cigarette smoking, hypertension, diabetes,           Small vessel calcification (calciphylaxis)
                                                          This is arterial calcification occurring in
obesity, hyperlipidaemia, lack of exercise and
                                                     chronic renal failure associated with
drugs (oral contraceptives and β-blockers).
                                                     hyperparathyroidism leading to infarction of
Patients usually present with intermittent
                                                     the skin on the inner thighs of women. The
claudication, but ischaemic ulceration or
                                                     prognosis is poor and treatment unsatisfactory.
infarction of the skin is the likely presenting
feature to the dermatologist. As the disease         Thromboangiitis obliterans
progresses, rest pain at night occurs in the foot          This disease (Buerger’s disease) is a
or calf. Altered skin color (pallor or deep          disorder of peripheral arteries of young males
erythema) indicate ischaemia and may be              who are heavy smokers. The aetiology is
accompanied by other skin trophic changes            unknown. Antiendothelial cell antibodies are
such as dryness, scaling, loss of hair and           present in high titre in active disease, may be
thickened nails. Patients with atherosclerotic       used to monitor disease activity, and may have
disease of the lower limb vessels usually have       a role in the pathogenesis. The histopathology
other arteries affected. The extent of atheroma      shows segmental or focal inflammation of the
in the coronary and carotid arteries                 full thickness of the vessel wall with cellular

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infiltrate (lymphocytes, eosinophils, plasma        controlled for 3 weeks by using epidural
cells and monocytes), especially disrupting the     block.
internal elastic lamina, and there is occlusion
                                                    Complex regional pain syndrome
as a result of highly cellular thrombosis.
                                                          This syndrome (causalgia) describes pain
Accompanying nerves and veins may be
                                                    and swelling aggravated by movement of an
involved in the inflammatory process.
                                                    affected limb. The skin is deep red or blue,
      The condition affects the fingers and toes
                                                    and warmer than the unaffected limb, but in
and presents as pain (of several types i.e.
                                                    the later stages becomes cooler. Oedema may
intermittent claudication, rest pain at night, or
                                                    result from dependency and disuse, and
pain associated with ischaemic neuropathy,
                                                    atrophy develops. The mechanism appears to
ulceration or thrombophlebitis); sensitivity to     be inhibition of cutaneous sympathetic
cold; claudication of the foot; ulceration or       vasoconstrictor neurones. Treatment includes
gangrene (of sides of the nails or tips of the      physical therapy, anticonvulsants, anti-
digits); trophic changes; acral color changes       depressants and then opioid analgesia
(asymmetrical, red or cyanotic); recurrent          according to severity. Severe cases may
venous thrombosis (superficial thrombo-             require regional anaesthetic blockade.
phlebitis with superficial red streaks and
cords, or deep vein thrombosis with pain and        Venous disorders
swelling); and the proximal pulses are usually      Introduction
present but the distal pulses are lost.             Anatomy
Arteriography shows normal proximal vessels              Compared with arteries, the walls of
while distal vessels show diffuse affection         veins are thinner, the middle (muscular) coat
with multiple stenoses and occlusions, and          being particularly weak. Most veins are
many collaterals are present. Conservative          endowed with semilunar bicuspid valves
treatment includes warmth, bed rest and             which are usually in pairs and are lined by
prohibition of smoking. Surgical or chemical        endothelium. They prevent the reflux of blood
sympathectomy using prostacycline analogue          and are particularly important in the leg,
are usually helpful. Anticoagulants do not          where their integrity, and that of the calf-
influence the outcome.                              muscle pumps (the venous heart), must
Erythromelalgia                                     effectively    counter    the     gravitational
     A condition of painful red hands and feet      hydrostatic pressure. There are 3 systems: the
precipitated by exercise or heat and relieved       deep veins, the superficial veins, and the
by rapid cooling, in which a sensation of           communicating veins, connecting the other 2
intense burning and warmth is associated with       systems. Valves may become damaged,
vasodilatation and erythema of the affected         thickened or degenerate with age. Thrombosis
skin. Affected persons have an undue                also causes valvular destruction, and a
sensitivity to warmth in the skin of the            canalized post-thrombotic vein is valveless,
extremities and there is temperature-triggered      anatomically distorted and functionally
release of chemical pain mediators and              ineffective.     Incompetence       of      the
vasoactive substances, especially serotonin,        communicating veins of the lower leg is a
                                                    predominant factor in venous ulceration.
due      to    post-ganglionic    sympathetic
dysfunction. Erythromelalgia may be primary,        Physiology
occurring in young subjects, or secondary,               In health, venous return occurs from
occurring over middle age and associated with       superficial to deep veins, the valves within the
other disease (e.g. thrombocythaemia,               communicating veins prevent blood passing
polycythemia vera, atherosclerosis, vasculitis,     from the deep veins into the superficial veins
diabetes and hypertension). Attacks last from a     of the legs. Muscular movement of the lower
few minutes to several hours. Patients prefer       leg causes a dramatic fall in venous pressure
immersion in cold water. Small doses of             which slowly returns to its original level after
aspirin are effective in some cases,                exercise ceases. In the absence of muscular
presumably by preventing platelet aggregation       movement, an increase in the leg volume
and clopidogrel may be a more effective             occurs without pitting oedema, and the tissue
antiplatelet    agent.     Propranolol      and     pressure rises considerably. Venous pressure
amitriptyline are often useful. Pain may be         at the ankle is normally 70-100 mmHg,


                                                -323-
dropping to 0-30 mmHg on exercise or                 paralysis or immobility, surgical procedures
recumbency, and remaining at 55 mmHg                 lasting more than 30 min, injuries especially
while sitting. There is a gradient of                tibial fractures, personal or family history of
permeability from arterioles to venules, with        thrombo-embolism, active cancer, hormonal
protein exchange occurring in the latter. The        influences (pregnancy, oral contraceptives,
blood enters the capillary bed under a               tamoxifen), infective fevers (e.g. typhoid), and
reasonably constant pressure, and local shifts       hypercoagulable states (antiphospholipid
in capillary pressure are introduced by              syndrome and the thrombophilias). The
changes in the resistance presented by the           thrombophilias are conditions that predispose
efferent venules.                                    to thrombosis and include protein C and S
                                                     deficiency, antithrombin deficiency and
Pathophysiology
                                                     activated protein C resistance.
      In patients in whom venous valves
                                                           Presentation of DVT may be with chest
become incompetent, blood is able to reflux
                                                     pain or cardiac arrest from pulmonary
back into the superficial veins, abolishing the
                                                     embolism, or with local calf manifestations
normal pressure drop that occurs on exercise
                                                     (calf is painful, tender, swollen, cyanotic and
and causing a persistently elevated venous
                                                     warm) with oedema of one ankle. Diagnosis of
pressure which affects capillary function. The
                                                     DVT is with duplex scanning. Complications
transluminal and intraluminal pressures
                                                     of DVT include pulmonary embolism,
increase, particularly at the venous end of the
                                                     recurrent thrombosis and post-thrombotic
capillary bed, encouraging more fluid and
                                                     syndrome. This syndrome results from high
electrolytes to enter the tissues. This results in
                                                     venous pressure secondary to damage to
oedema. In addition, the individual capillary
                                                     valves. Treatment of DVT is with
beds elongate and distend, allowing a larger
                                                     subcutaneous heparin once daily and warfarin
surface area for transluminal migration. As
                                                     treatment should be started after 24-48 h and
the capillaries distend, larger molecules and
                                                     continued for 3-6 months.
the cellular moieties of blood escape into the
interstitial fluid. Normally, these cells and        Superficial thrombophlebitis
macromolecules are broken down and cleared                There is both phlebitis and local
by macrophages and the lymphatics, but if            thrombosis. Clinically, there is severe pain,
sufficiently large quantities enter the              heat and tenderness overlying a palpable
interstitial fluid, the normal haemostatic           subcutaneous nodule or cord, without
mechanisms are swamped. This results in              lymphadenitis or peripheral limb oedema. The
accumulation of solid particles (e.g.                condition may occur in a varicose vein (most
fibrinogen) in the interstitial space around the     common) or be secondary to other causes e.g.
capillaries of the dermis. Fibrinogen forms          intravenous injection of an irritant drug,
insoluble pericapillary ‘fibrin cuffs’.              insertion    of an      intravenous   canula,
      There are several theories for                 malignancy, hypercoagulable states, or other
explanation of dermal hypoxia that causes            diseases (Behcet’s syndrome or Buerger’s
ulceration in chronic venous insufficiency,          disease). Spontaneous resolution usually
and none of them is completely accepted. The         occurs without anticoagulants, but NSAIDs
fibrin cuff theory denotes tissue inability to       are given for the pain.
lyse fibrin due to diminished production of          Post-thrombotic syndrome
plasminogen activators and increased level of              This     syndrome      causes       venous
inhibitors. A second theory is that there is         hypertension as a consequence of thrombotic
decreased oxygen uptake by the tissue                damage to valves. It complicates 50% of deep-
because high resting flows cannot increase           vein thrombosis. Consequences of post-
further to meet the demands of wound healing         thrombotic damage include further DVT,
following injury. A third theory is that there is    superficial thrombophlebitis, oedema, skin
local activation of neutrophils which cause          changes      from      venous      hypertension
white-cell plugging that impairs perfusion.          (lipodermatosclerosis,            subcutaneous
Venous thrombosis                                    calcification) and eventually ulceration.
Deep vein thrombosis                                 Thrombophlebitis migrans
    The risk factors for deep vein thrombosis             The superficial veins of the lower
(DVT) include obesity, varicose veins,               extremities, abdomen or elsewhere, undergo

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segmental thrombosis, causing crops of tender,      recurrence can be helped by below-knee
linear or oval subcutaneous lumps or streaks.       compression stockings.
The condition occurs with malignancy
                                                    Haemosiderin pigmentation
(especially cancer lung and pancreas),
                                                         Raised capillary pressure and vessel wall
hypercoagulable states and Behcet’s disease.
                                                    changes resulting from raised venous pressure
Clinical features of chronic venous                 permit red cell extravasation into the dermis,
insufficiency                                       leading to gravitational purpura on the antero-
Varicose veins                                      medial part of the lower leg. As red cells
      These are visible tortuous elongation and     degenerate so haemosiderin remains and a
dilatation of the larger superficial venous         brown pigmentation develops.
trunks of the legs and their tributaries. The
                                                    Pitting oedema
widening, elongation and tortuosity of the
                                                          Increased capillary filtration is a direct
venular end of the upper dermal capillary           result of raised capillary pressure and in turn
(capillary telangiectasia), the venules in the      of raised venous pressure. Pericapillary
subpapillary      plexus      (blue      venous     oedema occurs at an early stage of venous
telangiectasia) and the truncal varicose veins      disease. Pitting oedema does not occur until
are associated with venous hypertension.            the interstitial fluid volume has doubled. Any
Capillary telangiectasia are red, intradermal       oedema is the result of an imbalance between
and 0.1 0.4 mm in diameter. Larger                  capillary filtration and lymph drainage.
telangiectases (0.4 – 1 mm diameter) are dark       Oedema is worst at the end of the day and
blue and often palpable. Reticular varicose         usually disappears at night. It is mainly
veins are subcutaneous (2 – 4 mm in diameter)       present at the ankle. Varicose oedema should
and arise from small veins.                         be differentiated from venous oedema of right-
         Primary varicose veins are inherited       sided heart failure and oedema due to
and they are caused by hereditary structural        hypoalbuminaemia. Oedema affects the
defects of the vein walls. They are 3 times         nutrition of the epidermis and reduces
more common in women than in men, and               compliance of the skin, making it more
they often present for the first time in            susceptible to injury and eczema.
pregnancy, 20% of women being affected. The
most common cause of secondary varicose             Corona phlebectasia
veins is post-thrombotic syndrome. Varicose               An ankle flare (the corona phlebectasia)
veins may be a purely cosmetic problem but          is an early and important clinical sign of CVI
many patients also complain of aching pain          and is a direct consequence of increased
and oedema, worse at night.                         capillary pressure which causes these vessels
         Complications of varicose veins such       to expand.
as haemorrhage and thrombophlebitis, result         Varicose eczema (stasis dermatitis)
from the varicose veins themselves; oedema,              The presentation of varicose eczema is
haemosiderin pigmentation, varicose eczema,         variable and includes an acute weeping diffuse
atrophie blanche, lipodermatosclerosis and          eczema, discoid eczema, asteatotic eczema,
venous ulceration result from venous                chronic lichenified eczema, autosensitization
hypertension. Varicose veins are diagnosed by       eczema, contact allergic eczema from drugs,
color Duplex Doppler ultrasound scanning.           or secondarily infected impetiginized eczema.
      Patients complaining of aching pain and
oedema may benefit from venoactive drugs            Cellulitis
(e.g. coumarin, rutin) and compression                    The risk of cellulitis is increased in the
hosiery. Injection sclerotherapy is used to treat   presence     of     oedema      or     lymphatic
minor branch vein varicosities but not truncal      insufficiency. Typical lower leg cellulitis is
veins. Capillary telangiectases can be treated      characterized by pain, redness, swelling, fever
by microinjection therapy or laser. Venous          and rigors. Blistering and necrosis may occur
surgery is potentially curative for refluxing       if oedema is marked.
superficial veins when the deep veins are           Lipodermatosclerosis
competent.       Post-thrombotic      secondary          This     describes    the     progressive
varicose veins can be treated surgically e.g.       induration, inflammation and pigmentation,
valve transplantation, bypass grafts and            associated with excessive fibrosis of the skin


                                                -325-
and subcutaneous tissues, that is induced by        Leg ulcers
chronic venous hypertension. This is a                    Leg ulcers affect 1% of the adult
specific skin disorder that is pathognomonic        population, especially the elderly persons. The
of venous and lymphatic hypertension. It is a       main causes are venous hypertension
consequence of an increased matrix turnover         (commonest cause), arterial disease (next
caused by a chronic inflammatory reaction in        common cause), diabetes, but other causes
response to escaped plasma constituents. It is      also exist. The causes of leg ulcers include
associated with increased risk of leg ulcer         venous hypertension (varicose veins and post-
development. It occurs in acute and chronic         thrombotic syndrome), arterial disease
forms. The acute form is painful and                (atherosclerosis, hypertension), skin cancer
disabling, with plum-red skin which is              (basal and squamous cell carcinoma),
oedematous and very tender, and a firm mass         vasculitis (SLE, rheumatoid disease, systemic
with a distinct edge in the subcutis. The           sclerosis), blood disorders (protein C or S
condition occurs on the lower leg.                  deficiency, sickle cell disease, thalassemia,
Thrombophlebitis within superficial truncal         polycythemia, myeloma, cryoglobulinaemia),
veins usually coexists. Commonly mistaken           peripheral neuropathy (diabetes, leprosy),
as cellulitis, there is no fever, leukocytosis or   infections (ecthyma, tuberculous ulcers of
lymphadenitis, and the condition is frequently      erythema induratum, foot ulcers of leprosy,
bilateral. Antibiotics have no effect but           gummatous ulcers, leishmaniasis, phagedenic
elevation and reduction of venous pressure          ulcers in the seriously ill), traumatic and
often alleviate the symptoms. The chronic           factitious ulcers; drugs (hydroxyurea), genetic
form may develop de novo or follow the acute        ulcers (prolidase deficiency), and skin
form. The skin is thickened and tight, with         conditions        (pyoderma        gangrenosum,
fixed     to     hard,     indurated    fibrosing   necrobiosis lipoidica).
subcutaneous       tissue.    Progressive    sub-   Arterial ischaemic ulcers: These are very
cutaneous fibrosis gives the leg an inverted        painful and occur in the pretibial area or on the
‘champagne bottle’ shape. The skin is not red       toes, whereas venous leg ulcers favor the
but pigmented brown. Pitting oedema is              gaiter region. The ulcers are sharply defined
present in the calf above the affected area.        and punched out, the base is pale and covered
Atrophie blanche                                    with a slough, with minimal exudation and no
      This is a smooth ivory-white plaque of        pigmentation. The condition is indolent,
fibrosis, stippled with pinpoint telangiectases,    healing only when the blood supply is
surrounded by haemosiderin pigmentation,            improved and the ulcer is excised and grafted.
occurring on the lower leg or foot of women         Ulcers caused by vasculitis: These are usually
and caused by chronic venous insufficiency.         multiple and palpable purpura is characteristic.
The condition is symptomless unless painful         Ulcers of SLE usually affect the fingertips but
punched out ulcers occur. The histopathology        may affect the legs. Ulcers of rheumatoid
shows atrophic epidermis, scleroderma-like          arthritis are situated in the gaiter region and
changes in the dermis, and new vessel               have a sloughy base with poor granulation.
formation in the subpapillary layer. Protection     They are differentiated from venous leg ulcers
against trauma is essential to avoid ulceration.    by absence of signs of venous hypertension,
Treatment of pain is beneficial with                presence of a positive rheumatoid factor and
intralesional lignocaine or corticosteroids,        normal Doppler pressures. Healing is impaired
nicotinic acid, stanozolol, subcutaneous            because of muscle atrophy, immobility and
heparin 5000 i.u. twice weekly, or the use of       oedema. In Felty’s syndrome and still’s
                                                    disease, multiple painful ulcers occur on the
drugs that inhibit platelet aggregation.
                                                    legs and feet and are difficult to heal. Ulcers
Varicose ulcer                                      of livedo reticularis vasculitis are small,
     This is an end stage of CVI.                   painful and heal with ivory white scars
                                                    (atrophie blanche).
Secondary lymphoedema
                                                    Haematological ulcers: Indolent non-healing
      This may develop in patients with long-
                                                    ulcers on the leg are a feature of sickle cell
lasting CVI due to eventual obliteration of
                                                    anaemia and other haemolytic anaemias. In
lymphatic vessels.
                                                    thalassemia, the skin is shiny and pigmented.


                                                -326-
Traumatic ulcers: These are common on the           the site of injury. The facies are characteristic
shins and ankles and may follow fractures.          (hypertelorism and saddle nose) and other
Pressure sores occur on the heels and ankles of     associations      include      dental    caries,
elderly people, especially those who are            splenomegaly, respiratory infections and optic
paralyzed. Leg ulcers may be caused by              atrophy. Diagnosis is ascertained by
accidental burns, or be caused by artefact.         iminopeptiduria greater than 5 mmol/24h.
Neuropathic ulcers: These are most common           Because co-factors of prolidase are ascorbic
in diabetic subjects. About 70% of diabetic         acid and manganese, these have been a
foot ulcers are caused by neuropathy with           recommended          therapy,       as       has
adequate vasculature. Infection frequently          diphenylhydantoin. An ointment containing
coexist.                                            5% glycine and 5% proline may be effective.
Steroid ulcers: These are caused by                 Foot ulcer: Of all ulcers of the leg, 30% occur
intralesional or strong topical corticosteroids.    on the foot. Venous foot ulcers are unusual
They are indolent, with a characteristic greyish    and foot ulcers are usually caused by arterial
slough and suppressed granulation tissue.           insufficiency or peripheral neuropathy or both.
Infective ulcers: Infection may lead to leg         Lack of sensation makes the patient unaware
ulceration.    Meleney’s     ulcer    (bacterial    of infection or ulceration. The commonest
synergistic gangrene) extends rapidly and has       causes of foot ulcers include decubitus ulcers,
a burrowing, bluish, undermined and painful         diabetic ulcers and leprosy ulcers, and
edge. Tuberculous ulcers of erythema                infection, ischaemia and neuropathy are co-
induratum of Bazin occur on the back of the         working.
calves and have undermined edges. Ulcers of
leprosy occur usually on the foot.                  Venous leg ulcers
Pyoderma gangrenosum: May cause a rapidly           Introduction
spreading and often bizarre and extensive                These are caused by               capillary
ulceration, which may mimic an artefact.            hypertension resulting from persistently
Necrobiosis lipoidica: May ulcerate after           elevated venous pressure caused by
trauma.                                             incompetence of superficial veins (60%) or of
Hypertensive      ulcers:    Hypertension      is   deep veins (40%) after post-thrombotic
associated with reduced density of the dermis       syndrome. The condition has a maximal
capillary bed of the lateral aspect of the skin,    incidence in middle-aged or elderly women,
and this predisposes to ischaemic necrosis.         with a chronic or relapsing course, and is often
Hypertensive ulceration is more common in           exacerbated or originated by external injury.
women and tends to be bilateral. It produces        One-third of ulcers in elderly people have
superficial ulceration because the affected         coexisting arterial insufficiency as one factor
vascular bed is near the surface. The               contributing to their failure to heal. A family
peripheral pulses are always present,               history of leg ulcers is found in 50% of those
distinguishing      the     condition       from    affected. Once treated, 70% of patients can
atherosclerotic ulcers. The ulcer is often          suffer recurrence.
initiated by trauma. The ulcer occurs on the
anterior external aspect of the leg at a point      Clinical features
between the middle and lower thirds of the                The ulcer is characteristically situated on
limb. It is extremely painful, and this may be      the medial lower aspect of the leg, the gaiter
alleviated by holding the leg in the dependent      region. The skin around the ulcer is frequently
position. The livid edge is a characteristic        irritated by exudate from varicose eczema or
feature. The blood pressure should be               medicament eczema. Other signs of venous
controlled, and smoking and β-blockers              hypertension are usually present, including
avoided. A firm non-elastic support bandage,        varicose veins, varicose eczema, oedema or
without compression, is the most helpful            lipodermatosclerosis. Ulcers often show a
dressing. Excision with grafting has been           pseudoepitheliomatous hyperplasia at their
advised.                                            edge, which may be mistaken for a squamous
Prolidase deficiency: This is a rare autosomal      cell carcinoma. The ulcer bed is oedematous
recessive condition beginning in childhood,         with abundant newly formed capillaries lying
leading to recurrent ulceration of the skin.        in a granulation tissue covered by serous
Fragility of the skin results in break-down at      exudate or crust.

                                                -327-
Table 28.1 Differential diagnosis of the 3 major types of leg ulcers.
Item              Venous                      Arterial                               Neuropathic
Location          Medial malleolar region     Pressure sites, distal points (toes)   Pressure sites
Morphology        Irregular borders           Dry, necrotic base, ‘punched out’      ‘punched out’
Surrounding       Pigmentation secondary      Shiny atrophic skin with hair loss     Thick callus
skin              to haemosiderin,
                  lipodermatosclerosis
Other findings    Varicose veins Leg/ankle Weak/absent peripheral pulses,            Peripheral neuropathy
                  oedema, ± stasis            prolonged capillary refill time (>     with decreased
                  dermatitis ±                3-4 s), pallor on leg elevation (45º   sensation, ± foot
                  lymphoedema                 for 1 min), dependent rubor            deformities
       Healing ulcers have a shallow sloping              obliteration leads to attacks of cellulitis which
edge with healthy granulation in their base and           cause lymphoedema that delays ulcer healing.
little slough. By contrast, a non-healing ulcer           Malignant change is rare in venous leg ulcers
resembles severe paronychia, being boggy,                 and includes squamous and basal cell
undermined and congested. The coexistence of              carcinoma. Subcutaneous calcification occurs
arterial disease can contribute to the                    in 10% of patients with chronic venous
progression of a venous ulcer, and in such                insufficiency and may cause non-healing of an
cases, patients develop typical ischaemic pain            ulcer. Periostitis is commonly seen beneath a
on elevation of the ulcerated leg. To relieve             chronic ulcer. Osteoporosis results from disuse
pain, patients keep the leg in a dependent                atrophy. Osteoarthritis is a common
position and this exacerbates venous                      concomitant condition especially of the knee.
ulceration. Table 28.1 illustrates the
differential diagnosis of the 3 main types of             Management of venous leg ulcers
leg ulcers (venous, arterial, neuropathic).                     This includes general measures and
                                                          surgical treatment. General measures include
Associations                                              compression       therapy,     cleansing      and
     Venous leg ulcers can be associated with             debridement, dressings and topical therapy,
conditions that may prevent ulcers from                   treatment of infection, pain relief, and
healing by reducing peripheral oxygenation                systemic therapy. First-line therapy for venous
e.g. atherosclerosis, hypertension, obesity,              ulcers is compression therapy. This reduces
joint disease, anaemias (iron deficiency),                venous pressure, improves calf muscle pump
hypoalbuminaemia (poor diet), diabetes and                function and opposes gravitational venous
zinc deficiency. Oral zinc aid healing in                 reflux. Graduated multilayer high compression
patients with low serum zinc.                             bandage regimens capable of sustaining
Complications                                             compression for a week at a time should be the
      Venous leg ulcers may be complicated by             first line of treatment for uncomplicated
infection, contact dermatitis, lymphoedema,               venous ulcers. More patients were healed at
malignant change, subcutaneous calcification              12-15 weeks with high compression.
and bone changes. The role of antisepsis in the                 Exercise and movement are to be
healing of leg ulcers is much debated.                    encouraged, which long periods spent sitting
Pathogenic organisms are commonly found                   and standing are discouraged. When resting,
and the bacterial flora is often profuse.                 the legs should be elevated, ideally with the
However, certain infections should be taken               ulcer just above the level of the heart to insure
seriously including the group A β-haemolytic              the maximum reduction in venous pressure.
streptococci and Pseudomonas. Irritant contact            Thus, lying is always preferable to sitting with
dermatitis may result from the exudate and                the leg elevated. Conditions that exacerbate
allergic contact dermatitis due to medicaments            venous hypertension should be treated e.g.
(e.g. lanoline, parabens, topical anaesthetics,           heart failure and obesity. If eczema is present,
topical     antihistamines,    Dettol,  sodium            a topical steroid is indicated, whereas
fusidate, gentamycin, neomycin, framycetin)               emollients alone are sufficient for non-
may occur. Potent topical steroids on leg                 inflamed skin.
ulcers may inhibit healing leading to an                        Irrigation of the ulcer with warmed tap
arterial-type indolent steroid ulcer.                     water or sterile saline is usually sufficient for
         The superficial lymphatics are absent            cleansing. Strict antisepsis is unnecessary. It
in and around ulcers and their distortion or              is customary to remove sloughy or necrotic

                                                   -328-
tissue from the ulcer by debridement, as this        also a 50% recurrence rate after surgery within
improves wound healing. Dressings should be          5 years. Ligation and stripping of the
simple and low adherent. Ideally, a dressing         saphenous        veins     and      compressive
should be left undisturbed for as long as            sclerotherapy are the most frequently done
possible to allow ulcer healing. Frequent            procedures. It would appear that surgical
changes of dressing disrupt new fragile              eradication of superficial incompetent veins is
epithelium. Strike through of exudate to the         effective in preventing recurrent ulceration but
outside of a dressing bandage is usually an          is of little or no value in patients with post-
indication for a dressing change. Tissue-            thrombotic syndrome. These are treated with
engineered skin equivalent (e.g. Apligraft) has      stanozolol and stockings to prevent ulcer
been shown to aid healing over and above that        recurrence.
achieved by compression, and is particularly
effective      in    therapy-resistant     ulcers.
                                                     Telangiectases
Granulocyte-macrophage colony-stimulating            Introduction
                                                           These are chronically dilated capillaries
factor appears to promote healing of venous
                                                     or small venules, appearing on the skin and
ulcers.
                                                     mucous membranes as small, red, linear,
      Chronic leg ulcers are usually colonized
                                                     stellate or punctate markings, representing
by microorganisms and antibiotic therapy
                                                     dilatations (expansion, stretching) of pre-
should be started if there are clinical signs of
                                                     existing vessels without any new vessel
infection such as surrounding inflammation,
                                                     growth      (angiogenesis).    The      macular
redness or cellulitis, or increased pain, or
                                                     telangiectases     seen     in     scleroderma,
occurrence of a purulent exudate or fever.
                                                     generalized essential telangiectasia and nevus
      Most patients with venous ulcers suffer
                                                     flammeus are produced by dilatation of post-
moderate to severe pain. This can result in
                                                     capillary venules of the upper horizontal
immobility leading to a poor calf muscle
                                                     (subpapillary) plexus. Cherry angiomas are
pump. Pain may also indicate other pathology
                                                     produced by spherical and tubular dilatations
such as ischaemia, malignancy or infection.
                                                     of capillary loops in dermal papillae with
Analgesia is recommended if compression
                                                     cross-connections between individual loops.
fails to relieve pain. Opioids may be necessary
                                                     Angiokeratoma of Fabry and Fordyce have the
in some cases. Some deep pain may be
                                                     ultrastructure of collecting venules that
mediated by the autonomic nervous system
                                                     contain valves and appear to represent the
and may be helped by amitriptyline or a
                                                     ectopic development of small valve-containing
guanethidine block. Quinine is a useful
                                                     collecting veins. The cutaneous lesions of
therapy for night cramp.
                                                     hereditary     haemorrhagic       telangiectasia
      Some systemic drugs may accelerate
                                                     represent      microvascular      arteriovenous
healing of venous leg ulcers including
                                                     anastomoses.
pentoxifylline (800 mg 3 times daily), aspirin
(300 mg daily) and Daflon (500 mg daily).            Aetiology
      Once their ulcer is healed, patients should          Telangiectases may be primary or
be transferred from a bandage regimen to             secondary. Primary telangiectases include
compression hosiery, of which there are 3            spider          telangiectases,       angiomas,
categories depending on the severity of the          angiokeratomas, vascular naevi, angioma
venous hypertension. Hosiery should not be           serpriginosum,       hereditary    haemorrhagic
worn overnight. At least 2 pairs should be           telangiectasia,        generalized     essential
provided to allow for daily changing and             telangiectasia, ataxia telangiectasia, Bloom’s
washing. Two stockings per leg should last 6         syndrome and telangiectases occurring on
months before compression is lost and                exposed sites in patients receiving calcium
replacements are required.                           channel blocking drugs.
      About 50% recurrence rate of venous                  Secondary telangiectases include those
ulcers occurs over 5-years. Recurrence is more       following prolonged vasodilatation (rosacea,
likely in post-thrombotic limbs and may also         varicose veins), those due to physical agents
be caused by inadequate or worn-out hosiery,         (prolonged exposure to sunlight, post-
superimposed arterial disease or minor trauma.       traumatic, radiodermatitis), ageing, connective
Prophylaxis against recurrence by surgical           tissue diseases (nail fold telangiectases in
treatment is a matter of dispute since there is      SLE, dermatomyositis and systemic sclerosis,

                                                 -329-
eyelids    and     hands     telangiectases  in    diameter. They are grouped into areas a few
dermatomyositis, telangiectases of CREST           centimeters across, or form large sheets or
syndrome), Raynaud’s phenomenon (Face and          irregular lesions. Frequently, there is a
mucous membranes telangiectasia), cutaneous        background of diffuse erythema. The lesions
atrophy (Poikiloderma, topical corticosteroids),   may not blanch completely on pressure.
other skin diseases (xeroderma pigmentosum,        Characteristically, the lesions extend over a
telangiectasia macularis eruptiva perstans of      period of months or years then cease.
mastocytosis, HIV infection, and cosmetic          Individual     puncta        often   disappear
telangiectases on the lower limbs of women).       spontaneously, and complete regression of the
Cosmetic telangiectases may be present             eruption may occur. Differential diagnosis
individually, in sheets or as an arborising        includes angiokeratoma corporis diffusum,
appearance. Larger telangiectases (< 1 mm)         angiokeratoma circumscriptum naeviforme
are dark blue and palpable while smallest          and some types of capillaritis. Treatment is
telangiectases (0.1 mm), most superficial, are     with pulsed dye laser, if required.
red. They are treated with laser.
                                                   Hereditary haemorrhagic telangiectasia
Spider telangiectases                                    This disease (HHT, Osler-Rendu-Weber
      These telangiectases (spider naevus)         disease) is an autosomal dominant disorder
occur in 15% of normal persons, including          characterized by 4 criteria: epistaxis
children, during pregnancy and in liver            (spontaneous, recurrent), skin telangiectasia
disease. One or more spiders occur in two-         (very numerous, punctate or linear, anywhere
thirds of pregnant women and usually               but especially on the upper half of the body),
disappear within 6 weeks of delivery but may       visceral arteriovenous malformations in the
persist or occur in the same site in subsequent    lung (dyspnea, cyanosis, clubbing of the
pregnancies. The main vessel of the spider is      fingers), GIT (with or without bleeding), liver
an arteriole. The blood flows from this to the     (hepatomegaly, cirrhosis), cerebral and spinal,
periphery, and then passes into a capillary        and a positive family history (a first degree
network. Spiders vary in size and shape, and       relative with HHT). Mutations in 2 genes are
may be up to 1.5 cm across. The central body       associated      with    HHT.     Endoglin    on
may be raised, and is pulsatile on diascopy.       chromosome 9 is responsible for HHT-1
The radiating vessels are just visible to the      (higher pulmonary affection), while activin
naked eye. Spiders occur on the upper half of      receptor-like kinase on chromosome 12 is
the body, especially the face, neck and hands.     responsible for HHT-2 (milder phenotype and
They may be solitary or multiple. Spiders with     later onset). Both genes have been reported to
liver    disease    are    numerous.      Spider   be essential for angiogenesis.
telangiectases tend to persist indefinitely. The         Recurrent epistaxis is the presenting
central vessel of a spider naevus can be           symptom, usually at puberty, while skin
destroyed with electrolysis or pin-point
                                                   telangiectases usually appear in the third or
hyferication without anaesthesia. Lesions may
                                                   fourth decade. Lesions occur on the nasal
recur.
                                                   septum, mouth, and the tongue shows
Cherry angiomas                                    characteristic fungiform papilla expanded by a
     These are common on the trunk of              single much-dilated vessel. Haemorrhage may
middle-aged or elderly people. They disappear      occur from any site and may lead to iron
in extreme old age. Increased numbers occur        deficiency anaemia. In mild cases, no
in diabetics. They are treated by diathermy or     treatment is needed. Individual lesions may be
cautery.                                           destroyed with the cautery, diathermy or laser.
Angioma serpiginosum                               Anaemia should be corrected with iron
      This disease occurs predominantly in         replacement. Treatment of epistaxis may be
females (90%), and usually starts in               helped with oestrogens (induce keratinization
childhood. Histologically, dilated and tortuous    of the nasal mucosa), or the antifibrinolytic
capillaries are observed in the papillary          agent ε-aminocaproic acid. The mortality rate
dermis. The common sites are the lower limbs       is 10%. Pulmonary and other systemic
and buttocks. It is often unilateral initially.    arteriovenous malformations may be amenable
Lesions are red or purple puncta up to 1 mm in     to resection, ligation or embolization.


                                               -330-
Ataxia-telangiectasia                          especially characteristic. Defects of T and B
     In this rare recessive disease there is   lymphocyte cell function may also be present.
defective excision repair of DNA damaged by    The skin may be dry and prematurely grey
UV light. It consists of skin telangiectases   hair and eczematous lesions may occur. The
(develop between ages of 3 and 5 years,        use of gammaglobulin may be helpful.
occurring on the conjunctiva, eyelids, ears,   Generalized essential telangiectasia
checks and limbs), progressive cerebellar            This condition occurs in early adult life,
disease (onset second year of life, cause      more in females. There are extensive sheets of
ataxia, nystagmus and slurred speech),         linear telangiectases on the limbs or body. The
combined immunodeficiency (recurrent sinus     disease is of cosmetic importance only. Laser
and pulmonary infections), and a marked        treatment may be helpful but lesions tend to
susceptibility to cancer. Defective IgA is     relapse.




                                           -331-

				
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