Endocrine function in abetalipoproteinemia: a study of a female patient of Greek origin.

AIM: To investigate the pituary, genitalia, adrenal, thyroid, parathyroid and pancreatic endocrine function of a female patient aged 37 with abetalipoproteinemia at the time of diagnosis and 5 years thereafter (after application of a modified diet). SUBJECT-METHODS: Serum concentrations of cortisol, A4, ACTH, aldosteron, renin, dehydroepiandrosterone sulfate (DHEA-5), progesterone, 17-OH progesterone, testosterone, SH13G, estradiol, luteinizing hormone, follicle stimulating hormone, T3, T4, TSH, FT3, FT4, parathormone, osteocalcin, prolactin, proinsuline, insulin, glucagon, somatomedin-C (Insulin-like Growth Factor-1, IGF-1), IG171-13P3, 25 (OH) Vitamin D3 and 1-25 (OH) 2 Vitamin D3, were measured by radioimmunoassay. Synactlien test, and 24-hour urine cortisol, were also estimated. Serum leptin estimation was carried-out using a sensitive enzymatic technique. Ionized part of serum calcium was measured by the use of a special machine (CORNING), while bone alkaline phosphatase was measured by radioimmunoassay. RESULTS: Serum progesterone and 17-OH-progesterone were reduced in both examinations. Estimation of serum progesterone performed on the 21th day of the menstrual cycle revealed again values below the lowest normal limit. Serum prolactin was increased both in rest and during movement. The levels of both, somatomedin-C (IGF-1) and leptin were below the lowest normal limit. Despite normal serum parathormone, serum-ionized calcium and 25-OH vitamin D were low, while serum bone alkaline phosphatase was increased. Serum proinsulin was increased, and serum insulin was low. Serum thyroid hormone, glucagon, parathormone, FSH, LH, ACTH, testosterone, estradiol and SH13G were normal. The hormonal profile of the patient estimated 5 years later did not differ substantially suggesting that the metabolic improvement due to the adoption of the modified diet had not any significant impact on it. CONCLUSION: Female patients with abetalipoproteinernia have reduced production of progesterone by the corpus luteum and slightly abnormal bone metabolism. The reduced production of progesterone is probably due to the low levels of serum LDL and cholesterol, while reduced serum levels of Leptin and IG17-1 are probably due to the impairment nutritional status. The adoption of a modified diet does not alter the hormonal profile significantly.

A-beta-lipoproteinemia: clinical and laboratory features, therapeutic manipulations, and follow-up study of three members of a Greek family.

We describe the clinicoepidemiologic features, natural history, and therapeutic manipulations in three Greek patients with A-beta-lipoproteinemia (two brothers aged 15 and 29 years, respectively, and one sister aged 30 years). Diarrhea started in infancy in the two brothers and from the age of 13 in the sister. During the second decade of life, central nervous system symptoms became prominent, with fatigue and disturbance in gait and balance. Night blindness developed at a later phase of the disease in the brothers, whereas cavus developed in both legs in the sister. Apolipoprotein B was absent in all patients, and each had more than 50% of acanthocytes present on peripheral smear. The diagnosis of A-beta-lipoproteinemia was established on the basis of small bowel histology and serum lipid estimations. Family studies revealed normal lipid profiles in all healthy members. The human leukocyte antigen (HLA) pattern in the two most severely affected patients was identical. The only detectable difference between the severely ill patients and other members of the family, however, was homozygosity for the HLA B18 antigen, whereas the third patient had no alleles for the HLA B18 antigen. Treatment consisted of a low-fat diet and high doses of vitamins A and E. A modified diet substituting medium-chain triglycerides for dietary fat was also given, with significant improvement in the nutritional status of patients but not in symptoms related to advanced disease, such as retinal and cardiac manifestations. We conclude that the course of the disease in untreated patients is characterized by continuous symptoms. Some of the symptoms, however, especially those related to malabsorption, as well as some anthropometric parameters can be improved by the application of a modified diet including medium-chain triglycerides. We suggest the routine measurement of plasma lipids and apoproteins not only in children with failure to thrive, with unexplained malabsorption, or with neurologic symptoms, but also in adults with chronic diarrhea accompanied by neurologic symptoms or clinical and laboratory signs of malabsorption.