This paper presents clinical and laboratory data which indicate the development of a syndrome heretofore undescribed and still incompletely studied which appears in children during recovery from severe malnutrition. The principal clinical findings are portal-intrahepatic hypertension beginning 20 to 40 days after treatment is instituted and lasting about a month. Hepatomegaly, which is the first sign, is marked and progressive, affects particularly the left lobe and is inversely proportional to the degree of fatty infiltration of the liver, as is demonstrated by liver biopsies. Along with the hepatomegaly there is distention of the abdomen, a thoraco-abdominal venous network and ascites. Later phenomena (occurring after about 60 days of treatment) are hypertrichosis of the forehead, back and thighs, as well as a more or less marked eosinophilia not explained by intestinal parasites or allergy. The most important chemical finding is the hyper-gamma globulinemia, the highest level of which coincides with the appearance of the portal hypertension; this is definitely statistically significant. At the same time a considerable elevation of total plasma proteins takes place and thymol turbidity tests become progressively more abnormal.