James R. Humbert

Severe homozygous protein C deficiency

An infant with recurrent purpura fulminans in the first year of life was found to have severe homozygous deficiency of protein C (less than 1% of normal levels). The episodes of purpura fulminans were controlled by infusions of fresh frozen plasma containing protein C. The requirement of frequent plasma infusions, however, eventually resulted in several complications secondary to hyperproteinemia. Factor IX concentrates rich in protein C were then given to maintain adequate levels of the factor while minimizing the amount of extraneous proteins. The patient has remained asymptomatic and free of complications for greater than 10 months while receiving these concentrates every 48 hours.

Polycythemia in small for gestational age infants

Neonatal polycythemia and related disorders were studied in 23 full-term infants small for gestational age (SGA), 23 full-term (F-AGA), and 18 preterm infants of birth weights appropriate for gestational age (P-AGA). SGA infants had significantly higher hemoglobin, hematocrit, erythrocyte count, and fetal hemoglobin concentration values than other babies. Half of the SGA infants were polycythemic (venous hematocrit greater than 60 per cent). Four of them, all male infants, had important clinical problems including respiratory difficulties, priapism, hypoglycemia, and hypocalcemia. SGA infants also demonstrated a significant decrease in reticulocyte count after the first postnatal day. In all infants, capillary hematocrits were consistently higher than venous hematocrits. All male SGA babies should have hematocrit determinations shortly after birth and be observed closely for the development of clinical complications, particularly if polycythemic.

Trimethylamine N-oxide synthesis: A human variant

A 6-year-old girl exhibiting a variety of clinical symptoms including an apparant inability to metabolize trimethylamine has been shown to possess a defective liver trimethylamine oxidizing system. The defect manifested itself in a Km for trimethylamine which was five times that characteristic of normal enzyme preparation.

NEUTROPHIL BACTERICIDAL DYSFUNCTION TOWARDS OXIDANT RADICAL-SENSITIVE MICROORGANISMS DURING EXPERIMENTAL IRON DEFICIENCY

We developed a clear-cut nutritional iron deficiency anemia without concomittant malnutrition in rats given a low iron diet, and we restored normal iron and hemoglobin levels in these same animals with iron dextran injections. The neutrophil function studies performed during and after a period of iron deficiency showed the following: Phagocytosis of Staphylococcus aureus 502A, Streptococcus pneumoniae, and Salmonella typhimurium was not altered by iron deficiency or by the administration of iron; phagocytosis of Candida albicans was moderately abnormal during iron deficiency, and became normal with the restoration of iron sufficiency. Microbicidal activity towards Staphylococcus aureus 502A and Candida albicans, two catalase-positive microorganisms, was markedly decreased (to 50% of control values) and returned to normal when iron sufficiency was restored. Killing of a catalase-negative organism, Streptococcus pneumoniae was normal in iron-deficient rats. This pattern of differential bactericidal activities suggested an abnormality of the oxidant radical-generating machinery in neutrophils of iron-deficient animals. Indeed, iron deficiency caused a marked decrease of neutrophil nitroblue tetrazolium dye reduction, which disappeared after iron administration. Neutrophil myeloperoxidase activity was slightly decreased in iron deficient rats and returned to normal after iron administration. Microbicidal activity towards a gram-negative, catalase-positive organism, Salmonella typhimurium, was equal in iron deficient and iron sufficient animals. Our combined results suggest that a definite microbicidal defect is the consequence of nutritional iron deficiency, apart from any protein-calorie malnutrition. This defect affects the disposal in PMNs of two catalase-positive microorganisms (which require intracellular production of oxidant radicals for their destruction) but not of a catalase-negative bacterial species.(ABSTRACT TRUNCATED AT 250 WORDS)

Frequency of the carrier state for X‐linked chronic granulomatous disease among females with lupus erythematosus

Carriers for chronic granulomatous disease (CGD) and patients with lupus erythematosus (LE) share several characteristics: They are mostly females, they reduce nitroblue tetra‐zolium (NBT) poorly in their neutrophils, and, in some cases, they have similar skin lesions. We thus investigated 19 female LE patients for the presence of laboratory findings characteristic of the carrier state for CGD. None of these patients turned out to have the combined abnormality of neutrophil bactericidal activity and neutrophil NBT‐reduction that is diagnostic of CGD carrier state in the X‐linked form. An increased frequency of CGD carriers among female LE patients thus appears to be unlikely. Why some CGD carriers develop skin lesions typical of LE remains unexplained.

A hyperimmunoglobulin E syndrome with normal chemotaxis in vitro and defective leukotaxis in vivo

A 26-yr-old male with a lifelong history of atopic dermatitis and recurrent severe staphylococcal abscesses was found to have hyperimmunoglobulinemia E. Evaluation of both the humoral and cellular aspects of chemotaxis in vitro showed both neutrophils and monocytes to be normal. However, quantitative neutrophil migration in vivo was significantly suppressed using the patients own serum as the attractant. This defective migration in vivo was partially corrected by serum from normal donors as the attractant and also partially corrected following plasma infusion in this patient. Evaluation of quantitative leukocyte migration in vivo may be most useful in patients suspected of defects of leukocyte mobility.

Presymptomatic late-infantile metachromatic leukodystrophy treated with bone marrow transplantation

At 8 months of age, before clinical neurologic deterioration, the younger of two sisters with metachromatic leukodystrophy received a transplant of bone marrow from her haploidentical, heterozygote mother. Compared with the course in the older, affected, untreated sibling, the onset of neurologic regression was delayed 1 year and progressed at a slower rate.

Missing Y chromosome in juvenile chronic myelogenous leukemia

SummaryA child with Ph1-negative juvenile chronic myelogenous leukemia (CML) is presented. The only chromosomal abnormality in hematopoietic tissues consisted of an absent Y chromosome. While a missing Y chromosome in adult patients with CML may be associated with a better prognosis, the clinical course in our patient was as malignant as that usually observed in other children with Ph1-negative juvenile CML.This publication is No. 626 from the Department of Biophysics and Genetics, University of Colorado Medical Center.

Decreased neutrophil bactericidal activity in acute leukemia of childhood.

Neutrophil (PMN) bactericidal activity, phagocytosis, and nitroblue tetrazolium (NBT) reduction were evaluated in 18 children with untreated or relapsing acute leukemia and 20 children in hematologic remission. Half of the patients in relapse demonstrated abnormal PMN bactericidal activity, while remission patients had essentially normal PMN bactericidal activity. Phagocytosis of Staphylococcus aureus was normal in relapse and remission subjects. NBT reduction by PMNs of leukemic patients was significantly lower than that of controls, but there was no correlation between decreased NBT‐reductase activity and decreased bactericidal power. Six patients in remission had received intensive chemotherapy for more than 4 years, and all demonstrated normal PMN functions. Among relapse patients with abnormal PMN bactericidal activity 63% eventually developed severe bacterial infections. By comparison, 20% of the relapse patients with normal PMN bactericidal activity subsequently developed severe infections. The PMN dysfunction observed in relapse patients suggests that abnormal PMN bactericidal activity may contribute the increased susceptibility to bacterial infections during leukemic relapse.

[35] Intracellular killing of bacteria and fungi

Publisher Summary The measurement of bactericidal activity is considered the essential physiological tool that links the clinical expression of phagocytic defects with their biochemical and molecular etiology. Bactericidal activity measurements are often used as a diagnostic screening test in clinical medicine or as a logical source of reference when the inhibitors or enhancers of metabolic steps that influence bacterial killing in phagocytes are experimented. This chapter describes the intracellular killing of bacteria and fungi. It discusses three assay variants that should be applicable to most clinical or experimental laboratory situations. Killing assay using bacterial colony counts (Method 1) can easily be adapted for any bacterial strain by using modifications proposed by Leijh et al. The assessment of microbial killing by a fluorochrome assay (Method 2) is readily applicable to the study of fungi as well as bacteria and uses minuscule amounts of blood. A novel killing assay using a temperature-sensitive mutant as a target organism (Method 3) developed by Hooke confronts the problem of bacterial growth during the course of the assay.