Allosensitization in patients receiving multiple blood transfusions.

Extended antigen (C, E, K) matching decreased the incidence of alloantibody (alloAB) and autoantibody (autoAB) formation, in addition to eliminating transfusion reactions in the multiply transfused sickle cell disease patients. AlloAB formation possibly transforms the immune system into a hyperactive state leading to further and earlier alloAB and autoAB formation. However, additional CEK matching results in marked overuse of Rh-negative packed red blood cell (pRBC) units, 30 minutes' extra time of a skilled technologist, and 153 dollars extra CEK reagent cost per unit to find CEK-matched pRBCs for every transfusion for these multiply transfused patients.

Prevalence of penicillin-nonsusceptible Streptococcus pneumoniae in nasopharyngeal cultures from patients with sickle cell disease.

BACKGROUND: Prevention of pneumococcal sepsis in children with sickle cell disease (SCD) is threatened by the emergence of penicillin-nonsusceptible pneumococci. METHODS: In this study, nasopharyngeal colonization with Streptococcus pneumoniae and penicillin susceptibility were compared in children with SCD and a control group. Nasopharyngeal cultures were obtained from 130 children with SCD and 123 control children. Penicillin susceptibility was determined by Epsilometer test. Compliance with penicillin prophylaxis in SCD patients was determined by parent interviews and review of patients' medical and pharmacy records. RESULTS: Streptococcus pneumoniae was isolated from 8 (6%) of 130 SCD patients, and 21 (17%) of 123 control patients. Of the 29 S pneumoniae isolates, 6 (21%) were nonsusceptible to penicillin; 4 of 8 (50%) were from the SCD group and 2 of 21 (10%) from the control group. CONCLUSIONS: Penicillin prophylaxis decreased the rate of S pneumoniae colonization in SCD patients; however, it also increased the risk of selective colonization with penicillin-nonsusceptible S pneumoniae.

Hemophagocytosis and granulomas in the bone marrow of a child with Down syndrome.

Persistent fever with pancytopenia and hepatomegaly with negative blood cultures and no obvious focus of infection in a child with Down syndrome should arouse a suspicion of leukemia. Bone marrow examination and clot biopsy from one such patient revealed hemophagocytosis and granulomas, with serologic evidence of recent Epstein-Barr virus infection. Bone marrow granulomas are not a feature of Epstein-Barr infection. Later, bone marrow culture and repeat blood culture grew Salmonella typhi. Thus, in a febrile child, when performing a bone marrow aspirate, a clot biopsy and culture for infectious etiology may be helpful, even when leukemia is strongly suspected.

Proptosis: management of 22 patients.

The clinical features and management of 22 cases with proptosis is highlighted. Proptosis was unilateral in fifteen and bilateral in seven cases. The common etiologic factors were neoplasms, infections and bleeding diatheses. Of the ten cases with neoplasms as many as 7 expired, whereas of nine cases due to infections only one expired and one developed phthisis bulbi. All three patients with proptosis due to bleeds recovered completely without sequelae. Orbital CT scan was done in fourteen and ultrasound in eight cases, while in five cases both investigations were done. As neoplasms are a frequent cause of proptosis in children and there is a high mortality in this group, a thorough systemic examination and hematological profile is essential to arrive at a speedy diagnosis. CT and USG are useful imaging modalities of the orbit, the latter being particularly useful for follow up of the lesion.

Prophylactic theophylline infusion for prevention of apnea of prematurity.

To assess if there was any advantage in the prophylactic use of theophylline to prevent apnea in preterms, we treated 56 preterms (Group A) < 34 weeks gestation with theophylline infusion and compared these with 25 age and weight matched preterms (Group B) who received no therapy. Aminophylline (25 mg/ml) was infused from admission in all neonates (group A) at rates ranging 0.2 to 0.38 mg/kg/h and blood levels estimated on an Abbots TDX analyser by Fluorescence Polarization Immunoassay, after 5 days infusion. All neonates (Groups A + B) were monitored on a Corometric 505 neonatal monitor. In Group A, 1/48 developed primary apnea while in Group B, 4-21 had primary apnea (p < 0.05). Serum theophylline ranged from 2.3 to 39.5 micrograms/ml with a mean of 12.7 micrograms/ml. The mean serum level of theophylline in 4 cases who exhibited clinical evidences of toxicity was 30.1 micrograms/ml. A statistically significant difference (p < 0.05) was noted in birth weight and serum level inspite of similar infusion rates of theophylline. A linear correlation r = 0.65 was noted between serum level and infusion rate. Multivariate regression analysis, between birth weight and gestational age to serum level, showed a linear correlationship only between birth weight and serum level (r = 0.45).

Neonatal gastrointestinal perforations.

Fourteen neonates presented with clinical and radiological evidence of gastrointestinal perforation, of which 13 were treated by operative intervention. No infant was formula fed, had rectal bleeding or radiological evidence of pneumatosis intestinalis. Operative findings revealed localized perforation in ten of which three were gastric, two distal ileal, three cecal and two in sigmoid colon. Gangrene with extensive perforation of jejunum, ascending colon and transverse colon were seen in one each. Blood cultures were positive in four, one grew E. coli and three Klebsiella while peritoneal cultures were positive in six, one grew E. coli and five Klebsiella. Ten neonates survived and are being followed up. Three of the four cases who died had white blood cell count greater than 25 x 109/L and grew Klebsiella on peritoneal culture. Factors predisposing to gastrointestinal perforations in neonates are discussed, emphasis is made on the cautious use of umbilical, gastric and rectal catheters, and the need for early surgical intervention.

Hematocrit and whole blood viscosity in newborns: analysis of 100 cases.

Hematocrit (Hct) and whole blood viscosity was studied at a mean age of ten hours in 100 neonates. Group A (n = 25), were term normal newborns, Group B (n = 25) were preterms, Group C (n = 20) were term small for gestation (SGA) and Group D (n = 30) had perinatal hypoxia. Blood viscosity was estimated in all cases at shear rates 94.5, 51.2, 20.4 and 8.1 and intergroup variability in viscosity compared at shear rate 51.2. The mean hematocrit (Hct) (59.4%) and viscosity (8.2 cps) was higher in Group A as compared to other groups, but the difference was not significant (p greater than 0.05). The upper limit of viscosity in Group C (11.9 cps) was higher than in all other groups but this difference was also not significant (p greater than 0.05). With decrease in shear rates a reciprocal increase in viscosity was noted in all four groups. Seventeen neonates (17%) had polycythemia of which eight (47.5%) were SGA. Twelve per cent preterms were polycythemic. Only 3% of neonates had hyperviscosity. The mean Hct and viscosity of the 17 cases with polycythemia was 70.9 and 9.21 cps, respectively, which was significantly higher than mean Hct and viscosity of Group A (p less than 0.05). Partial exchange transfusions were done in five neonates with Hct greater than 75%, of which only one had hyperviscosity. Post-exchange viscosity was not estimated. Whereas, three neonates with polycythemia were symptomatic, none of these had hyperviscosity. A linear correlation between Hct and viscosity was observed (r = 0.67).

Exchange transfusions via peripheral vessels.

During a 15 month period, partial exchange transfusions (ET) were done in 40 neonates with polycythemia, and double volume ET attempted in 7 neonates with hyperbilirubinemia via peripheral vessels. The procedure was effective and not associated with any complications for partial ET. During double volume ET minor complications were noted in 2 cases, both of whom recovered and subsequently successfully underwent supraumbilical ET. Of the 5 cases who had uneventful double volume exchanges, there was a significant drop in indirect serum bilirubin following the procedure. The mean pre-ET serum indirect bilirubin in these 5 cases was 334 mumol/L and mean post-ET level was 179 mumol/L with a mean drop of 155 mumol/L (46% drop). Technical difficulties in catheterization may be overcome with greater expertise and use of heparin to flush arterial catheters.

Therapy of symptomatic patent ductus arteriosus in preterms using mefenemic acid and indomethacin.

Mefenemic acid (MA) was given in three doses of 2 mg/kg/dose at 12 hourly intervals in 16 cases clinically suspected of having symptomatic patent ductus arteriosus (PDA). All babies were 35 weeks gestation (mean 30.1 weeks) and weighed less than or equal to 1700 g at birth (mean 1320 g), the mean age of administration of MA being 16 days. Of the 16 cases, two did not respond to therapy. One non-responder was subsequently shown to have an endocardial cushion defect without PDA on 2-D Echo and Doppler study. The other was 29 days old at the initiation of therapy. In once case, the ductus reopened after an initial closure, however, it closed on repeating a second course of the drug. Thirty preterms (less than or equal to 34 weeks) who were earlier treated with three doses of indomethacin (0.25 mg/kg/dose) formed the comparative study group. The closure rate of PDA on treatment with indomethacin was 70% and that with MA was 93.3% (p greater than 0.05). Two neonates treated with MA and two treated with indomethacin had feeding intolerance and vomiting, perhaps attributable to the drug therapy. We recommend the use of MA for closure of symptomatic PDA in preterms, especially in those cases where indomethacin is not tolerated or when minute titration of its dosage is impracticable.