Malnutrition: a cause of elevated sweat chloride concentration

In order to document the frequency and causes of elevated sweat chlorides we reviewed all sweat chloride determinations performed over a 2-year period. Seven hundred and thirty-five quantitative tests were performed. Three hundred and three positive or borderline results were obtained from 133 patients. Thirty-three of these patients did not have clinical evidence of CF. Fourteen of them (42%) suffered from malnutrition or growth stunting when tested. The remaining patients who were normally nourished, represented a very heterogeneous group with no unifying diagnosis. Initial sweat chlorides in 11/14 malnourished children were in the abnormal range (greater than 60 mmol/l). These tended to revert to normal coincident with improvement in nutritional status. Less remarkable elevations in sweat chloride levels were noted in the normally nourished patients, since almost 50% (9/19) were in the intermediate range (50-60 mmol/l). We conclude that malnutrition can be the cause of elevated sweat chlorides, which may lead to an erroneous diagnosis of cystic fibrosis. Clinicians should be aware of this association and adhere to strict criteria for the diagnosis of cystic fibrosis. Also, repeated sweat chloride determinations should be obtained, preferably following re-nutrition.     

Triosephosphate isomerase deficiency with elevated sweat chloride test: report of a case

A 15-month-old girl with severe hemolytic anemia and progressive respiratory failure is presented. She was well until the age of six months when she developed a pulmonary infection. During the next six months, she had frequent respiratory infections and her paleness became evident. At the age of 12 months, she was observed to have easy fatigability and muscle weakness, and she received her first blood transfusion. She was referred to our hospital at the age of 15 months. The physical examination revealed a malnourished girl with hypotonia, nystagmus, generalized muscle weakness and severe breathing difficulty requiring ventilatory support The hemoglobin (Hb) was 9.7 g/dl; hematocrit (Hct) 29%, mean corpuscular volume (MCV) 101 fl and reticulocyte count 15%. Peripheral blood smear revealed macrocytosis and stomatocytosis (30% of the red cells) and polychromasia. Sweat chloride test was 90 and 94 mEq/L on two separate occasions. The serum vitamin E level was 0.26 mg/dl (N: 0.44-0.68). She was found to be heterozygous for factor V Leiden mutation. Although malnutrition, low serum vitamin E and elevated sweat chloride test were suggestive of cystic fibrosis, this diagnosis failed to account for all the findings in the patient. A search for a red cell enzyme deficiency revealed that the red cell triosephosphate isomerase (TPI) activity was low. DNA analysis showed the 315 G-C (105 Glu-Asp) TPI mutation, thus confirming the diagnosis of TPI deficiency.     

Urolithiasis and enteric hyperoxaluria in a child with steatorrhea

Malabsorptive states are frequently associated with increased urinary oxalate excretion. The authors describe a 10-year-old girl with steatorrhea, hyperoxaluria, and a renal calculus in a single functioning kidney. Successful management of steatorrhea corrected both the chronic diarrhea and hyperoxaluria. Enteric hyperoxaluria is a well-known etiology of calcium oxalate urolithiasis in adults. Pediatricians caring for children with malabsorptive conditions should be aware of the risk of urinary calculus formation as a result of increased dietary oxalate absorption.     

Intestinal malignant lymphoma in a child with familial celiac disease

A case of intestinal malignant lymphoma occurring in a 10-year-old North African girl with celiac disease is reported. Celiac disease was diagnosed at age 4. A gluten-free diet was started and was maintained for the next 6 years. Seven months after the patient returned to a normal diet, clinical symptoms and subtotal villous atrophy relapsed. Within the next month an abdominal malignant lymphoma was diagnosed. After chemotherapy the tumor disappeared but recurred 6 months later, involving the colon and the liver. Death occurred shortly thereafter. A brother, two years older, also with proven celiac disease, is presently on a strict gluten-free diet. Both children shared the same histocompatibility antigens (HLA A2-B17/A29-B12, identity at the D locus). Whether or not relapse of celiac disease played a role in the appearance of the tumor remains highly speculative; however, the case of our patient suggests that familial involvement and, in some instances, ethnic origin may constitute risk factors predisposing to malignancy.     

Aneurysmal bone cyst of the femur in a child with celiac disease

A case of aneurysmal bone cyst of the femur in a 2-year-old boy with celiac disease is described. The bone cyst presented with a pathological fracture while the boy was undergoing gluten challenge. The definite diagnosis of celiac disease according to the criteria formulated by the European Society for Paediatric Gastroenterology and Nutrition was established. A hypothetical association between the two disorders is discussed.     

Myopathy and elevated serum enzymes in a case of hypoparathyroidism

A relation between hypocalcemia and myopathy could be demonstrated by clinical and laboratory evidence in an 8-year-old girl. Clinical and laboratory results are discussed in respect to the specific problems of pediatric membrane physiology.     

Folic acid concentration in the serum and erythrocytes of patients with celiac disease

In 16 children with coeliac disease consecutively diagnosed on the basis of 3 peroral small bowel biopsies in a period of 3 years 13 (81%) had low levels of folic acid in the serum (norm. reference range: 1.8-9 ng/ml) and in erythrocytes (norm. reference range: 150-450 ng/ml cells). The determination of folic acid has a better diagnostic value as the one-hour-D-Xylosetest. The low level of folic acid is the most constant nutritional deficiency in our group of coeliac patients. The determination of folate in the serum and erythrocytes is a highly sensitive screening and at the time it will indicate the adequate therapy.     

Proton MRS of a child with Sandhoff disease reveals elevated brain hexosamine.

Sandhoff disease (gangliosidosis type 0) is a lysosomal storage disorder with a deficiency of hexosaminidases A and B. After an initially normal development the clinical course of affected children is severe and rapidly progressive leading to spastic tetraparesis, epileptic seizures and early death. In a 10-month-old girl with enzymatically established diagnosis of Sandhoff disease MRI of the brain showed signal changes in the periventricular white matter, pyramidal tract, basal ganglia, and cerebellar hemispheres. Proton MR spectroscopy (MRS) at the age of 13 months revealed a reduction of total N-acetylaspartate (neuroaxonal marker) as well as strongly elevated inositol (glial marker) in white matter, gray matter, and basal ganglia. A new resonance at 2.07 ppm was detected in all regions and ascribed to N-acetylhexosamine with highest concentrations in white matter and thalamus. While conventional MRS findings are in line with neuroaxaonal damage and pronounced astrocytosis, the observation of N-acetylhexosamine appears as a specific marker of Sandhoff disease indicating accumulation of hexosamine-containing oligosaccharides. This interpretation is supported by a recent in vitro MRS study of a Sandhoff mouse model. In conclusion, proton MRS of cerebral metabolites offers specific insights into the pathopysiologic processes of children with Sandhoff disease and may prove to represent another disease specific MRS pattern of the brain.