[Idiopathic CD4(+)-T-lymphocytopenia]. / Idiopathische CD4(+)-T-lymfocytopenie.

Three patients, two men aged 27 and 33 years and one woman aged 31 years, developed several opportunistic infections without presence of HIV infection. Patient A died after suffering Candida stomatitis, extrapulmonary Mycobacterium avium infection, cytomegalovirus infection and Aspergillus pneumonia; patient B recovered from a disseminated M. kansasii infection; patient C suffered from verrucae planae. These patients had CD4(+)-T lymphocytopenia, a shortage of helper T cells. Idiopathic CD4(+)-T lymphocytopenia is a heterogeneous pathological condition with normal serum immunoglobulin concentrations. Treatment consists of combating and preventing infections.

Heterozygous and homozygous factor H deficiency states in a Dutch family.

Factor H, a 150-kD protein, is an important down-regulating protein of the alternative pathway of the complement system. Presently, only 15 persons, representing seven families, have been described with homozygous factor H deficiency. Deficiency of this protein, inherited as an autosomal recessive trait and resulting in uncontrolled breakdown of C3, results in depletion of components of the alternative pathway (factor B, properdin) and of the terminal pathway (C5), and is associated with the onset of bacterial infections, glomerulonephritis and systemic lupus erythematosus (SLE). The proband of the family in this study suffered from subacute cutaneous lupus erythematosus and had had meningococcal meningitis due to serogroup X. She had a complete factor H deficiency at the protein level as determined by Western blotting. Among 21 relatives of the proband studied, encompassing three generations, 10 had low factor H levels, including the two children of the proband, indicating a heterozygous factor H deficiency state. In serum samples of the proband and 11 relatives prospectively studied, a strong correlation of factor H levels with C3, C3 haemolytic activity, factor B and properdin levels (P < 0.0001) was found. Alternative pathway protein levels were significantly lower (Mann-Whitney test; Z values 3.6-2.7) in sera from the four heterozygous relatives studied than in sera from the seven non-deficient relatives. In addition, a defect of the 37/42-kD H-related protein was found in the proband and two of 21 relatives, compared with four of 40 controls. A defect of the 24/29-kD H-related protein was present in one of 21 relatives studied and in none of the 40 controls.

Terminal deoxynucleotidyl transferase positive subpopulations occur in the majority of ANLL: implications for the detection of minimal disease.

A series of 60 acute nonlymphocytic leukemias (ANLL) was analyzed for the expression of terminal deoxynucleotidyl transferase (TdT). The detected TdT+ cells were studied in detail by use of double marker analyses for TdT and differentiation markers, such as myeloid markers (CD13 and CD33), B cell markers, T cell markers, and the precursor antigen CD34. In 15 (25%) of these leukemic cell samples, we found no TdT+ cells or low percentages of CD10+TdT+ cells; the latter probably represent precursor B cells. In the other 45 (75%) ANLL myeloid marker+TdT+ CD10- cells were detected, ranging from 0.1-10% (n = 24) or over 10% (n = 21) of mononuclear cells. Interestingly, a higher frequency of CD34 positivity was found on the TdT+ cells as compared to the TdT- cells, suggesting that the TdT+ cells represent an immature leukemic subpopulation. Therefore, it may be speculated that the TdT+ subpopulation contains the clonogenic ANLL cells. In two patients, in whom immunologic marker analysis was performed at initial diagnosis as well as at relapse, an expansion of the TdT+ subpopulation was documented at relapse, which may reflect a reduced differentiation capacity of the leukemic cells. Previous studies on a series of nonleukemic bone marrow and blood samples revealed that normal counterparts of myeloid marker+TdT+ cells are rare in bone marrow (less than 0.03%, if they occur at all) and that such cells are not detectable in blood. Therefore myeloid marker TdT double stainings may be useful to monitor the TdT+ leukemic subpopulation in patients with a TdT+ ANLL during and after chemotherapy. Our preliminary results on the follow-up of two such patients support this hypothesis.

The determination of reference values for hematologic parameters using results obtained from patient populations.

Reference values for hematologic parameters are determined using data from patient populations of a whole year. As a consequence, the authors are not dependent on a limited selected population and can determine reference values for all age and sex groups. It turns out that from the possible compilation technics the gamma distribution gives the best fit. If the results are compared with values stated in the literature, it is remarkable that the total number of leukocytes for men older than 50 years is higher than for women; both the absolute and relative amount of monocytes and eosinophilic granulocytes are higher for men than for women. The platelets are lower for men than for women from the age of 15 years on.