Learning Center
Plans & pricing Sign in
Sign Out

Hereditary C1q deficiency: a new family with C1qA deficiency


A global leader in serving libraries of all types, ProQuest LLC (“ProQuest”) supports the breadth of the information community with innovative discovery solutions that power the business of books and the best in research experience. More than a content provider or aggregator, ProQuest is an information partner, creating indispensable research solutions that connect people and information. Through innovative, user-centered discovery technology, ProQuest offers billions of pages of global content that includes historical newspapers, dissertations, and uniquely relevant resources for researchers of any age and sophistication—including content not likely to be digitized by others.

More Info
  • pg 1
									The Turkish Journal of Pediatrics 2010; 52: 184-186                                                       Case

Hereditary C1q deficiency: a new family with
C1qA deficiency
Çağman Sun-Tan1, Tuba Turul Özgür1, Gamze Kılınç1, Rezan Topaloğlu2, Özay Gököz3,
Sibel Ersoy-Evans4, Özden Sanal1
Divisions of 1Immunology and 2Nephrology, Department of Pediatrics, and Departments
of 3Pathology, and 4Dermatology, Hacettepe University Faculty of Medicine, Ankara,

                            SUMMARY: Sun-Tan Ç, Turul-Özgür T, Kılınç G, Topaloğlu R, Gököz Ö,
                            Ersoy-Evans S, Sanal Ö. Hereditary C1q deficiency: a new family with C1qA
                            deficiency. Turk J Pediatr 2010; 52: 184-186.
                            Hereditary deficiency of complement component C1q is a rare genetic disorder
                            with susceptibility to recurrent infections with polysaccharide-containing
                            encapsulated microorganisms and a high prevalence of autoimmune diseases,
                            most often systemic lupus erythematosus (SLE). Here, we report a 29-
                            month-old boy who presented with facial rash and history of early death
                            of a sibling with infections, who was found to have a selective deficiency
                            of C1q. The facial rash was composed of patchy erythematous plaques and
                            centrally hypopigmented macules and desquamation. Two siblings had died
                            of severe bacterial infections and his uncle had died of meningitis. Molecular
                            study disclosed a homozygous point mutation in the C1qA chain gene. Five
                            members of the family, including the parents and three healthy siblings, were
                            heterozygous for this mutation.
                            Key words: C1q deficiency, C1qA chain, infection, systemic lupus erythematosus.

The complement system is a group of plasma                 whereas two siblings and an uncle had died
and cell surface proteins acting in the innate             of severe infections.
immune system. It not only contributes to
clearance of immune complexes and bacteria                 Case Report
via adherence, opsonization and microbial                  A 29-month-old boy was referred to Hacettepe
lysis, but also induces cellular and humoral               University Children’s Hospital with rash and
immune response producing anaphylatoxins                   desquamation on his face. Family history
and chemotactic factors. The complement                    revealed that the parents were consanguineous
component C1q initiates the classical pathway              and two siblings had died of infections (Fig. 1).
of complement activation by binding to immune              A brother experienced pneumococcal meningitis
complexes1-3. Deficiency of the complement                 at the age of four years, and a few weeks later
C1q is a rare genetic disorder with susceptibility         he died with a clinical picture of sepsis, and a
to recurrent infections with encapsulated                  sister who had undetectable total complement
microorganisms and a high prevalence of                    hemolytic activity (CH50) died of sepsis a
To top