M R MORSYETAL. Hyperammonemia in Marasmic Children by M. R. Morsy, MD, H. Madina, MD, S. A. Sharaf, Phd, A. T. Soliman, MD, M. M. Elzalabany, MD, and M. A. F. Ramadan, MD Departments of Pediatrics and Clinical Pathology, Unioersity of Alexandria, School of Medicine, Loran, Alexandria, Egypt Summary Tbe amino acids citrulline, ornfthine and arginine, total serum proteins, serum enzymes glutamic oxalacetic and glutamic pyruvic transaminases, blood ammonia and urea were measured in 20 marasmic children with manifest psycboraotor changes, before and after nutritional rehabilitation, as well as in 10 healthy age-matched children. Serum protein levels were significantly low and plasma ammonia concentrations were significantly elevated in marasmic children before refeeding (177 + 66 /ig/dl). Plasma ammonia concentrations decreased significantly after 4 weeks of nutritional rehabilitation (38 ±18 /Jg/dl). Tbe levels of blood area, serum enzymes, citrulline arginine, and ornithine did not differ among tbe study groups. These findings denote that hyperammonemia in marasmic children is neither due to defective hepatic function nor due to enzymatic blockade in tbe urea cycle. Introduction Psychomental changes are common in severe protein energy malnutrition (PEM). These changes range from remarkable silence and anorexia in mild cases to apathy, irritability, misery, and peevishness in severe cases. 1 Variable aetiologies have been proposed to explain the cause of these psychomotor changes, including blood ammonia concentrations, 2 because even minute quantities of ammonia are toxic to the central nervous system. Blood ammonia arises from three sources: ammonia formed in the tissues, ammonia produced by intestinal bacterial flora from dietary proteins, and ammonia produced by the kidneys. 3 The liver is considered the main site of detoxification of ammonia to urea in man. This cycle involves five enzymatic reactions in the liver mitochondria.*' 5 A fatty liver is characteristic of PEM. On micro- scopic examination the individual hepatic parenchy- mal cells appear distended with fat. Mitochondria, the site of urea cycle degenerate, first decrease in number, and then distort, cavitate, and finally disappear. 2 To investigate the urea cycle and liver function in severely malnourished children with psychomotor changes we measured the circulating levels of ammo- nia, urea, citrulline, ornithine, arginine and hepatic transaminases in 20 marasmic children with psycho- motor symptoms before and after improvement (4 weeks). Patients and Methods Twenty children with severe PEM between the age of 10 months and 2 years were admitted and studied in Correspondence: A. T. Soliman, University of Alexandria, 3 Abd El Sattar Mansour St, Loran, Alexandria, Egypt. Alexandria University Children's Hospital. Psycho- mental changes were manifest in all the studied cases. Ten age-matched healthy children served as controls. Informed consent was obtained from the parents of all the studied children and the study protocol was approved by the ethical committee of Alexandria University. All children were examined clinically with special emphasis on the nutritional data and signs of PEM. 6 The anthropometric measurement included weight, length, and mid-arm circumference. Har- pender's calipers and anthropometric measurements were used. Data recorded were the average of three sequential measurements determined by the same observer. After an overnight fast venous blood samples were obtained for determination of serum proteins, 7 gluta- mic oxalacetic transaminase (SGOT), glutamic pyru- vic transaminase (SGPT), 8 blood urea, 9 plasma ammonia, 10 and the amino acids citrulline, arginine and ornithine. 11 After 4 weeks of providing a high protein diet (1.5-2 g/kg/day) and improvement of psychomental changes all laboratory tests were repeated. Statistical analyses were done using the paired t-test before and after refeeding and unpaired t-test for the comparison among the two study groups. Results The anthropometric data of the control and marasmic children before and after nutritional rehabilitation for four weeks are presented in Table 1. The weight of marasmic children as percent of average for age ranged between 41 and 50 per cent. Laboratory results for the study groups are shown Journal of Tropical Pediatrics Vol. 40 April 1994 © Oxford University Press 1994 97 at Hamad Medical Corporation on November 19, 2013 http://tropej.oxfordjournals.org/ Downloaded from