Community-Acquired Pneumonia
Type Epidemiology Clinical Features Treatment
Streptococcal Prevalent in winter, Abrupt onset, toxic Penicillin
pneumonia occurs more appearance, Usually nonresistant—
(Streptococcus frequently in involves one or penicillin G,
pneumoniae) African Americans, more lobes, lobar amoxicillin
greater incidence in infiltrate common Penicillin
pt with COPD, heart on chest x-ray or resistant—
failure, alcoholism, bronchopneumonia cefotaxime,
asplenia, diabetes, pattern ceftriazone, or
and after influenze, fluoroquinolone
leading infectious
cause of illness
worldwide,
mortality in
hospitalized adults
with invasive
disease: 14%
Haemophilus Incidence greater in Frequently insidious Non-beta-lactamase
influenzae alcoholics, elderly, onset associated producing—
patients in long term with upper amoxicillin
care facilities, pt respiratory tract Beta-lactamase
with diabetes or infection 2-6 wks producing—2nd or
COPD, children before onset of 3rd generation
younger than 5 illness, fever, chills, cephalosporin,
years old, accounts productive cough, amoxicillin-
for 5-20% of CAP, usually involves one clavulanate
mortality rate: 30% or more lobes,
bacteremia is
common, infiltrate,
occasional
bronchopneumonia
patter on chest x-ray
Legionnaires’ Highest occurrence Flulike symptoms, Fluoroquinolone,
disease (Legionella in summer and fall, high fevers, mental azithromycin
pneumophila) may cause disease confusion,
sporadically or as headache, pleuritic
part as an epidemic, pain, myalgias,
greater incidence in dyspnea, productive
middle-age and cough, hemoptysis,
older men, smokers, leukocytosis,
pt with chronic bronchopneumonia
diseases, those (unilateral or
receiving bilateral, lobar
immunosuppressive consolidation)
therapy, and those
close in proximity to
excavation sites,
15% of CAP,
mortality rate: 15-
50%
Mycoplasma Increased incidence Onset is usually Macrolide, a
pneumoniae in fall and winter, insidious, patients tetracycline
responsible for not usually as ill as
epidemics of in other
respiratory illness, pneumonias, sore
most common type throat, nasal
of atypical congestion, ear pain,
pneumonia, headache, low-grade
accounts for 20 % fever, pleuritic pain,
of CAP, mortality myalgias, diarrhea,
rate: less than 0.1% erythematous rash,
pharyngitis,
interstitial infiltrates
on chest x-ray
Viral pneumonia Incidence greatest in Patch infiltrate, Oseltamivir or
(influenza types A, winter, epidemics small pleural zanamivir, treated
B adenovirus, occur every 2-3 y, effusion on chest x- symptomatically,
parainfluenza, most common ray, in most does not respond to
cytomegalovirus, causative organism patients, influenza treatment with
coronavirus, in adults, accounts begins as an acute currently available
varicella-zoster) for 20% of CAP upper respiratory antimicrobials
infection; others
have bronchitis,
pleurisy, and so one,
and still others
develop
gastrointestinal
symptoms
Chlamydial Reported mainly in Hoarseness, fever, Fluoroquinolone
pneumonia college students, chills, pharyngitis,
(Chlamydohilia military recruits, rhinitis,
pneumoniae) and the elderly, may nonproductive
be a common cause cough, myalgias,
of CAP or observed arthralgias, single
in combination with infiltrate on chest x-
other pathogens, ray, pleural effusion
mortality rate is low possible
because the majority
cases are mild, the
elderly with
coexistent
infections,
comorbities, and
reinfections may
require
hospitalization
Hospital-Acquired Pneumonia
Type Epidemiology Clinical Features Treatment
Pseudomonas Incidence greatest in Diffuse Antipseudomonal beta-
pneumonia those with consolidation on lactam plus
(Pseudomonas preexisting lung chest x-ray, toxic ciprofloxacin,
aeruginosa) disease, cancer, appearance: fever, levofloxacin or
homograft chills, productive aminoglycoside
transplants, burns, cough, relative
debilitated people, bradycardia,
pts receiving leukocytosis
antimicrobial therapy
and treatments such
as tracheostomy ,
suctioning, and in
post-op settings,
almost always
nosocomial in origin,
accounts for 15% of
HAP, mortality rate:
40-60%
Staphylococcal Incidence greatest in Severe hypoxemia, Methicillin
pneumonia immunocompromised cyanosis, susceptible—
(Staphylococcus pts, IV drug users, necrotizing antistaphylococcal
aureus) and as a complication infection, penicillin
of epidemic bacteremia is Methicillin resistant—
influenza, commonly common vancomycin or
nosocomial in origin, linezolid
accounts for 10-30%
of HAP, mortality
rate:25-60%,
methicillin-resistant
S. aureus (MRSA)
may also cause
community based
infection
Klebsiella Incidence greatest in Tissue necrosis Meropenem or
pneumonia elderly, alcoholics, pt occurs rapidly, levofloxacin or
(Klebsiella with chronic disease toxic appearance: piperacillin/tazobactam
pneumonia such as diabetes, fever, cough, plus amikacin
[Friedlander’s heart failure, COPD, sputum production,
bacillus- pts in chronic care bronchopneumonia,
encapsulated facilities and nursing lung abscess, lobar
gram negative homes, accounts for consolidation,
aerobic bacillus]) 2-5% of CAP and 10- bronchopneumonia
30% of HAP, patter on chest x-
mortality rate: 40- ray
50%
Pneumonia in the Immunocompromised Host
Type Epidemiology Clinical Features Treatment
Pneumocystis Incidence greatest in Pulmonary Trimethoprim/
pneumonia (PCP) pt with AIDS and pt infiltrates on chest sulfamethoxazole
(Pneumocystis receiving x-ray, (TMP-SMZ)
jiroveci) immunosuppressive nonproductive
therapy for cancer, cough, fever,
organ transplantation, dyspnea
and other disorders,
frequently seen with
cytomegalovirus
infection, mortality
rate 15-20% in
hospitalized pts and
fatal if not treated
Fungal pneumonia Incidence greatest in Cough, hemoptysis, Voriconazole or
(Aspergillus immunocompromised infiltrates, fungus anidulafungin or
fumigatus) and neutropenic pts, ball on chest x-ray caspofungin,
morality rate: 15- lobectomy for
20% fungus ball
Tuberculosis Incidence increased Weight loss, fever, Isoniazid plus
(Mycobacterium in indigent, night seats, cough, rifampin plus
tuberculosis) immigrant, and sputum production, ethambutol plus
prison populations, hemoptysis, pyrazinamide
people with AIDS, nonspecific
and the homeless, infiltrate (lower
mortality rate: less lobe), hilar node
than 1% (depending enlargement,
on comorbidity) pleural effusion on
chest x-ray
Pneumonia from Aspiration
Type Epidemiology Clinical Features Treatment
Anaerobic bacteria Risk: reduced Abrupt onset of Clindamycin or
(S. pneumonia, H. consciousness, dyspnea, low-grade beta-lactam
influenzae, S. dysphagia, disorders fever, cough, antibiotics
aureus) of upper GI tract, predisposing
mechanical condition for
disruption of glottic aspiration
closure
(endotracheal tube,
tracheostomy,
nasogastric feeding)