Biomedical subjects
Publications and source records attributed to I Tezcan.
A 2-month-old SCID patient with mesangial sclerosis of the kidney is presented. Although the ADA status of the patient is unknown, the parents' RBC-ADA levels seemed to be in the heterozygote range.
Immunoglobulin G (IgG) subclass levels were determined in 393 serum samples of 329 healthy children from birth to 16 years of age, 24 healthy adults and 20 pairs of mother-cord blood by radial immunodiffusion. Age-normal percentile values for IgG1, IgG2 and IgG3 were calculated for age-groups up to 16 years and for adults. The broad range of IgG4 values in children did not permit calculation of reference values.
Presented here is a 17-month-old adenosine deaminase-deficient, severe combined immunodeficient patient with chest symptoms, oral ulcer, neurologic manifestations, head lag, spasticity and developmental delay in motor functions. Antibiotics, systemic antifungal agents, intravenous immunoglobulins and partial exchange transfusions with irradiated fresh red cells were given. No other mode of therapy for adenosine deaminase (ADA) deficiency was available at that time. Amelioration of neurologic manifestations within one month of therapy with irradiated fresh red cell exchange transfusions suggests that these manifestations may have resulted from accumulated toxic metabolites. However, no improvement was seen in the course of infection and oral ulcer, and the patient died of respiratory failure on the 48th day of admission.
Low expression of T-cell receptor-CD3 (TCR-CD3) complex, a rare cause of combined immunodeficiency, has only recently begun to be recognized. Here we report a four-year-old boy who has defective TCR-CD3 complex expression presenting with recurrent chest infections and pulmonary symptoms implying bronchial asthma. In our opinion, this entity should be borne in mind as the possible underlying defect in children with combined immunodeficiency having signs and symptoms of humoral immunodeficiency.
Serum opsonization of yeast (Saccharomyces) was investigated in 51 patients whose ages were between six and 48 months (median 15 months) with acute purulent otitis media and in an age-matched control group (median 13 months). Opsonization was assessed by measuring yeast particle uptake in an assay based on an electronic count of the unphagocytosed particles in serum by polymorphonuclear leukocytes. Despite normal levels of CH50 and serum immunoglobulins, a defective opsonization was determined in 13.7 percent of the patients (7 in 51). The corresponding figure was 2.9 percent in 103 healthy controls (p < 0.001). On the other hand, 218 percent (5 in 23) of the children having a history of recurrent purulent otitis media showed defective opsonization (p < 0.001). Previously, the presence of an opsonization defect has been linked to low levels of mannan binding lectin (MBL), a calcium dependent serum lectin that acts as an opsonin. Therefore, our findings indirectly support the idea that MBL has an important role as host defense, particularly in the earlier period of life when the antibody repertoire is restricted.