Statistics from Altmetric.com
Editor,—Neutral lipid storage disease (NLSD) is an autosomal recessive metabolic disorder characterised by a multisystem accumulation of neutral lipids (triglycerides). The patients with NLSD have congenital ichthyosis and variable systemic manifestations.1 The storage of cytoplasmic triglycerides in NLSD patients results either from a severe defect in the degradation of cytoplasmic triacyglycerols containing long chain fatty acids2 or rapid triacyglycerol resynthesis.3Based on these biochemical data, one might expect that a low fat diet poor in long chain fatty acids could be beneficial to these patients. We report a boy with NLSD with emphasis on his response to dietary intervention.
An 8 year old boy was born as a collodion baby to unrelated parents. Examination at the age of 22 months revealed ichthyosiform erythroderma, hepatomegaly (11 cm below the right costal margin), and diffuse bilateral cataracts. Liver enzymes were raised (aspartate aminotransferase (AST): 177 IU/l, alanine aminotransferase (ALT): 179 IU/l, γ-glutamyltransferase: 42 IU/l. Liver histology showed gross fatty infiltration of the hepatocytes with lobular fibrosis. Leucocyte neutral lipid vacuolation was detected in the peripheral blood smears. Lipid thin layer chromatography from skin tissue showed increased accumulation of triglycerides.
The boy was put on a low fat diet (table 1) and at the end of the first year of treatment the size of the liver decreased by 50% and the liver function improved. The skin also became less erythematous and less scaly.
At the age of 3.5 years the boy was operated for cataracts. At the age of 8 years, still on the special diet, his skin condition improved further and the liver size was normal (AST: 60 IU/l, ALT: 70 IU/l). There was no hearing or muscle power impairment and he made good progress in school.
In our patient a low fat diet, poor in long chain and enriched with medium chain fatty acids, led to regression of liver size, improvement of his skin condition, and possibly prevention of other organ involvement. In 1980 Angelini et al also reported improvent in liver size with a medium chain triglyceride diet in a 5 year old girl with NLSD.4 As in other metabolic disorders the special diet did not restrain the progress of the patient’s cataracts.5 It is conceivable that by starting the special diet before cataract initiation, this complication might be totally prevented. This observation indicates that in cases of NLSD, an early initiation of a diet poor in long chain fatty acids might improve the skin condition and prevent systemic disturbances.