The incidence of renal calcification in preterm infants

A total of 79 infants born at less than 32 weeks' gestation were studied with serial renal ultrasound scans to assess the incidence of nephrocalcinosis. Twenty one infants developed renal calcification giving an overall incidence of 26.6% in the study group. Affected infants were significantly smaller (mean (SD) birth weight 940 (323) g) and significantly less mature (mean (SD) gestation 26.9 (1.9) weeks). In 17 patients the calcification was represented by hyperechogenic renal pyramids alone, and in four patients renal calculi were demonstrated. Factors associated with renal calcification included hypophosphataemia, hypercalcaemia, hypercreatininaemia, and prolonged oxygen requirement during the first month of life. Multivariate analysis showed that the strongest clinical indicator of calcification was duration of oxygen treatment. Infants who still required oxygen treatment at 28 days had a 62% chance of developing renal calcification.

Relation of behavioral treatment to "normal functioning": comment on Lovaas

Our commentary is a critique of the Lovaas (1987) study on the outcome of intensive behavioral intervention with young autistic children. Problems in the following aspects of the study are reviewed: (a) the choice of outcome measures, (b) the criteria for subject selection and the intellectual level of the subjects, and (c) the method for assigning subjects to control groups. Based on the available data, we posit that it is not possible to determine the effects of the intervention.

Relation of behavioral treatment to "normal functioning": Comment on Lovaas

Our commentary is a critique of the Lovaas (1987) study on the outcome of intensive behavioral intervention with young autistic children. Problems in the following aspects of the study are reviewed: (a) the choice of outcome measures, (b) the criteria for subject selection and the intellectual level of the subjects, and (c) the method for assigning subjects to control groups. Based on the available data, we posit that it is not possible to determine the effects of the intervention.

Pulmonary accumulation of polymorphonuclear leukocytes in the adult respiratory distress syndrome

The polymorphonuclear leukocyte (PMN) plays an integral role in the development of permeability pulmonary edema associated with the adult respiratory distress syndrome (ARDS). This report describes 3 patients with ARDS secondary to systemic sepsis who demonstrated an abnormal diffuse accumulation of Indium (111In)-labeled PMNs in their lungs, without concomitant clinical or laboratory evidence of a primary chest infection. In one patient, the accumulation of the pulmonary activity during an initial pass suggested that this observation was related to diffuse leukoaggregation within the pulmonary microvasculature. A 4th patient with ARDS was on high-dose corticosteroids at the time of a similar study, and showed no pulmonary accumulation of PMNs, suggesting a possible reason for the reported beneficial effect of corticosteroids in human ARDS.

Case studies: games: three examples from biochemistry, physiology and pharmacology

In the last issue Anthony Short and David Tomlinson (1980) gave an introductory discussion of the use of games in medical education. Here, with Michael Billet and Judyth Aarons, they give a detailed description of three games which currently form part of the curriculum at the University of Nottingham Medical School.

Urinary excretion of cyclic AMP in bacterial infections

Urinary cyclic AMP excretion was found to be increased in patients with severe bacterial infections and normal renal function. The observed changes appeared due to a combination of an increased filtered load plus augmented "nephrogenous" production in some patients; while in others, only an increase in the apparent "nephrogenous" production of cAMP could be found to account for the elevation in the total urinary excretion. Since total serum calcium was found to be low in most of these patients, increased PTH secretion to reduce urinary excretion of calcium may have been responsible for an increase in renal parenchymal production, and subsequent excretion of cyclic AMP. Although speculative, this theory is tenable in that ionized hypocalcemia exists in septic patients.

Variations in adrenocortical responsiveness during severe bacterial infections. Unrecognized adrenocortical insufficiency in severe bacterial infections

Plasma cortisol levels and their response to .25 mg synthetic A.C.T.H. (Cortrosyn) were studied in 26 septic patients. Four (15.4%) of these patients appeared to have greatly increased adrenocortical activity with plasma cortisol levels averaging 65.4 +/- 14.8 microgram/dl (normal = 8-18 microgram/dl. All four of these patients were agonal and died within five days. Seventeen (65.4%) of these 26 patients appeared to have an appropriate adrenocortical response to severe infection in that their plasma cortisol levels increased (averaging 19.2 +/- 6.0 microngram/dl) following synthetic A.C.T.H. The remaining five patients, who constituted 19.2% of the 26 patients studied, appeared to have some impairment of adrenocortical function. In spite of severe bacterial infections and no history to support Addison's disease, their plasma cortisol levels (averaging 13.8 +/- 3.3 microgram/dl) were not increased above normal and their response to Cortrosyn was much less than would be expected; the increase in plasma cortisol levels in these patients following the synthetic A.C.T.H. averaged 1.1 +/- 3.6 microgram/dl. It is reemphasized that patients with severe sepsis who are not responding adequately to standard therapy should be suspected of having adrenocortical insufficiency and treated accordingly.

Variations in plasma levels of adenosine 3',5'-monophosphate during clinical sepsis

Plasma levels of adenosine 3',5'-monophosphate were measured in 43 patients with bacterial infections of varying degrees of severity. The most severely ill patients, who died within 48 hours of study, had the highest levels of plasma adenosine 3',5'-monophosphate, 38.4+/-29.8 picomoles per milliliter. A significant and progressive decrease in plasma adenosine 3',5'-monophosphate level toward normal was found with lesser degrees of sepsis. However, even those patients who survived exhibited elevations of plasma adenosine 3',5'-monophosphate levels, 12.9+/-5.4 picomoles per milliliter, significantly above normal. Shock and impaired renal function appeared to contribute to the elevated levels found in the most severely ill patients. In those less severely ill, with normal renal function and no shock, the plasma adenosine 3',5'-monophosphate level was still significantly elevated above normal, suggesting that severe bacterial infection itself contributes to the generation of elevated plasma adenosine 3',5'-monophosphate levels. Various hormonal changes or increased cellular permeability, or both, may account for some of the increase of this intracellular nucleotide in the plasma. It is suggested that extremely high levels of plasma adenosine 3',5'-monophosphate are indicative of a poor prognosis.