Dietary calcium intake in rural black South African children. The relationship between calcium intake and calcium nutritional status.

Dietary calcium intake in relation to calcium status in rural black South African children was investigated. Fifteen subjects in each age group, 3-5 years, 8-10 years, 13-16 years with lowered serum calcium (less than 2.25 mmol/l) and raised serum alkaline phosphatase (greater than 300 i.u./l) were matched with controls having normal serum biochemistry. A dietary interview and 24-h recall was conducted with each subject; nutrient value of the diet was calculated from standard food tables. At 3-5 years, although the study group had significantly lower calcium intakes, there was no significant relationship between dietary calcium intake and calcium status. Study children in the age groups 8-10 years and 13-16 years had significantly lower dietary calcium intakes than controls and dietary calcium intake showed significant correlation with serum calcium levels, serum alkaline phosphatase levels, bone mineral density, metacarpal cortical thickness and calcium excretion. Thus it appears that low dietary calcium intakes may be reflected by hypocalcaemia, elevated alkaline phosphatase and decreased bone mineral content in pre-adolescent children.

Mechanisms of anemia in protein-energy malnutrition in Johannesburg.

Studies of red cell metabolism, erythropoeitin concentration, iron and folate status were made in 48 children with protein-energy malnutrition in Johannesburg (altitude 1800 m). Biochemical evidence of iron deficiency was presented in 26% cases on admission and developed in 90% during recovery. Biochemical evidence of folate deficiency was present in 14% of cases on admission and resolved on dietary therapy alone. Serum erythropoeitin was increased on admission and remained elevated during recovery. There was no relationship between serum erythropoeitin and Hb concentrations. Key enzymes in the red cell glycolytic and hexose monophosphate pathways and red cell membrane showed increased activity. Red cell adenosine triphosphate concentration was increased and unstable. Red cell potassium was decreased and, in the fatal cases, red cell sodium was increased. The possible significance and practical implications of these findings are discussed.

A demographic and socio-economic profile of a rural black South African community.

Demographic data regarding households in a Black rural community in the Eastern Transvaal were collected. Detailed socio-economic and health data were collected from a 10% random sample of households (response rate 92,5%). These data will be used for planning and evaluating a community health project. An extremely high infant mortality rate (198,1/1 000 live births), very low household incomes (median monetary household income R20 - R50 per month), low rates of immunization (39,4% of children under 12 years old had not been immunized), and gaps between the knowledge and practice of and the expressed desire for family planning were striking features.

Antipyrine pharmacokinetics and D-glucaric excretion in kwashiorkor.

Hepatic microsomal oxidation and glucuronidation were studied in 15 children with kwashiorkor on admission to the hospital and again after 3 weeks of nutritional rehabilitation. Microsomal oxidation as measured by antipyrine half-life and clearance was shown to be depressed in the acute phase of malnutrition (T 1/2 = 7.9 +/- 5.0 hr, clearance = 8.4 +/- 5.1 ml/min) improving with nutritional rehabilitation (T 1/2 = 4.3 +/- 2.3 hr, clearance = 15.5 +/- 8.7 ml/min). Urinary D-glucaric acid excretion increased from 60.6 +/- 42.2 mumoles/24 hr to 121.8 +/- 105.0 mumoles/24 hr over the same time period. Evidence is thus presented that both hepatic microsomal oxidation and glucuronidation are depressed in the acute phase of kwashiorkor but recover with nutritional rehabilitation.

Penicillin pharmacokinetics in kwashiorkor.

Intravenous penicillin kinetics have been studied in eight children with kwashiorkor on admission to hospital and when rehabilitated. A 75% increase in penicillin clearance was observed with recovery, associated with a fall in half-life; this was probably due to an improvement of both renal plasma flow and tubular function. The present observations and those of other authors working in this area are discussed and an approach to drug dosage of renally excreted drugs in kwashiorkor has been proposed.

Gentamicin pharmacokinetics in kwashiorkor.

1 Single dose intravenous gentamicin kinetics (2.4 mg/kg) were studied in six children with kwashiorkor. It was observed, that therapeutic drug concentrations were achieved which should be neither oto- nor nephrotoxic. 2 Due to the diminished glomerular filtration and renal plasma flow seen in the acute phase of kwashiorkor, gentamicin half-life was prolonged (229.0 +/- 94.8 min) at this time returning to normal (178.5 +/- 99.5 min) with nutritional rehabilitation.

Serum and salivary digoxin concentrations in children.

Serum and salivary digoxin concentrations were measured in 53 children and correlated with ECG variables and serum potassium, calcium and magnesium concentrations. In 73% of patients cardiac failure was controlled, while only 7,5% of patients had serum digoxin concentrations within the 'therapeutic range'. It is proposed that the adult therapeutic range of 1-2 ng/ml is not applicable to children, who can be controlled at lower concentrations and/or that a significant proportion of the children studied no longer required maintenance digoxin therapy.

Isoniazid pharmacokinetics in kwashiorkor.

Isoniazid plasma half-life and clearance rates were studied in children with kwashiorkor before and after nutritional rehabilitation. Isoniazid half-life rates fell and clearance increased with nutritional rehabilitation. The changes documented in this report are not an indication that isoniazid therapy should be altered in malnourished children, but may indicate that this should be done in malnourished adults.

Antipyrine elimination in critically ill patients.

Antipyrine kinetics were studied in 12 critically ill patients. Antipyrine half life was found to be short (6.5 +/- 3.4 h), this did not alter over 4 days of acute illness, although there was a tendency for antipyrine clearance to decrease over that time period. The need for further pharmacological studies in critically ill patients is stressed.

The metabolism of phenobarbitone, phenytoin and antipyrine in Black patients.

The half-lives of phenytoin, phenobarbitone and antipyrine were studied in adult Black patients to attempt to ascertain the cause of low phenytoin concentrations previously found in Black epileptics. The following half-life values were observed: antipyrine 5,7 +/- 1,9 hours, phenytoin 15,9 +/- 7,9 hours, phenobarbitone 63,0 +/- 18,2 hours, and phenytoin after 1 month of phenobarbitone therapy 31,5 +/- 11,9 hours. No explanation was obtained for the low phenytoin levels previously observed.

Gastrointestinal absorption studies in cardiac cachexia.

The nutritional status of 11 patients with severe mitral valve disease was investigated pre-operatively and 3 months post-operatively. It was shown that they were malnourished pre-operatively, and that this appeared to be related mainly to anorexia.

A socio-economic, health and cultural survey in Soweto.

The socio-economic, health and nutritional status of 186 families in Diepkloof, Soweto, was studied. The results, detailed in the text, reveal considerable socio-economic ills, of which the most important is the observation that 30% of the families existed below the poverty datum line, even when there was more than one wage-earner. More emphasis on health education and the promotion by health personnel of a better understanding of the backgrounds of clinic and hospital patients are urgent priorities for health services.

Serum levels of anticonvulsants and haematological sequelae in black epileptics.

Serum levels of phenytoin and phenobarbitone were studied in a group of Black adult epileptics. Therapeutically satisfactory levels of phenytoin were observed in only 11,3% of patients, and of phenobarbitone, in 63,9%. An overall non-compliance rate of about 50% was noted. The possible reasons for this are discussed. Folate deficiency was not a major problem in this group of patients.

A laboratory investigation into bilirubin binding in neonates.

The presence of free bilirubin the serum of 59 Black neonates was studied at the time of exchange transfusion with an electrophoretic technique. It was observed that 32 infants had detectable free bilirubin in their serum and that these infants had a significantly greater bilirubin/albumin ratio that infants without free serum bilirubin.

Hypoglycaemia associated with severe kwashiorkor.

A study was designed to investigate the hypoglycaemia of severe kwashiorkor. The findings of significant stores of hepatic glycogen suggests that glycogenolysis was impaired. Plasma glucagon levels were relatively low, and it is suggested that this might be secondary to either a pancreatic alpha-cell defect, or inadequate sympathetic stimulation.

Organic acidaemia in intensive care unit patients.

Forty ICU patients were studied as to the prevalence and importance of organic acidaemia. It was observed that organic acidaemia was extremely common, secondly that a persistence of such an acidaemia heralded a poor prognosis and finally that the acidaemia rarely needed treatment in its own right.

Experimental salicylate intoxication in young baboons. A preliminary report.

Salicylate intoxication has been investigated in young baboons. The results of these studies are similar to these previously obtained in man. Acidosis appears to be of considerable importance in the pathogenesis of infantile salicylism as it enhances the passage of salicylate into the CSF. The CSF concentration of salicylate seems to be of major physiologic importance in this condition. Moreover, the serum concentration of free salicylate correlates more closely with the CSF concentration of salicylate than does the total serum concentration of salicylate.