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Increased 5alpha-reductase and normal 11beta-hydroxysteroid dehydrogenase metabolism of C19 and C21 steroids in a young population with polycystic ovarian syndrome

Chin D; Shackleton C; Prasad VK; Kohn B; David R; Imperato-McGinley J; Cohen H; McMahon DJ; Oberfield SE
OBJECTIVE: To test the hypothesis that 5alpha-reductase (5alphaR) and 11beta-hydroxysteroid dehydrogenase (11beta-HSD) activity are increased in adolescent and young-adult women with PCOS and that an altered regulation of the hypothalamic-pituitary-adrenal (HPA) axis occurred in these subjects. DESIGN: Prospective non-randomized study in an academic research environment. PATIENTS: Eleven women, aged 14 to 25 years, were studied who were at least one year post-menarche and who had a diagnosis of PCOS based on a history of oligomenorrhea and elevated total and or free serum testosterone. INTERVENTION: 24-Hour urinary metabolites were assessed in nine subjects and five underwent stimulation with ovine corticotropin releasing factor (oCRF). OUTCOME MEASURES: C19 and C21 steroid urinary metabolite 5-alpha/5-beta pairs, 11-oxo/11-hydroxy products and the ratio of the total 5-alpha/5-beta reduced and 11-oxo/11-hydroxy products were compared to values in control women. Urinary cortisol (F) (sum of conjugated and free, and free F) and total F metabolites (the sum of THE, THF, 5alpha-THF, cortolones, and cortols) were determined. A 1 microg/kg oCRF stimulation test was performed with timed samples determined for plasma ACTH and serum F levels. RESULT: The 24-hour total and free urinary F were not different from control. However, the total F metabolites were markedly elevated (7922+/-2666 vs 5418+/-1549 microg/24 h, p<0.01). A marked increase in the total 5-alpha reduced C19 and C21 metabolites was observed in the PCOS population vs control (5084+/-1977 vs 2681+/-1188 microg/24 h, p<0.01). The total urinary 11-oxo/11-hydroxy metabolite ratio was not different, p=0.23. The basal values and response of both ACTH and F to oCRF stimulation were not different from those of controls. CONCLUSION: There is a marked increase in 5alphaR metabolism of both C19 and C21 steroids in younger women with PCOS
PMID: 10714750
ISSN: 0334-018x
CID: 11803

Thyroid dysfunction as a late effect in survivors of pediatric medulloblastoma/primitive neuroectodermal tumors: a comparison of hyperfractionated versus conventional radiotherapy

Chin D; Sklar C; Donahue B; Uli N; Geneiser N; Allen J; Nirenberg A; David R; Kohn B; Oberfield SE
BACKGROUND: Primary hypothyroidism is a common sequela of craniospinal radiotherapy in the treatment of pediatric brain tumors. METHODS: The authors compared the incidence of primary hypothyroidism after hyperfractionated radiotherapy (HFRT) (n = 14 patients) versus conventionally fractionated radiotherapy (CRT) (n = 34 patients) in a group of pediatric patients with medulloblastoma/primitive neuroectodermal tumors (MB/PNET). RESULTS: The mean age at the time of tumor diagnosis was 7.9 years in the HFRT group and 8.4 years in the CRT group. The patients were followed for a mean of 4.6 years (HFRT) and 8.3 years (CRT) after diagnosis. Mean radiation doses to the thyroid were similar in both radiotherapy groups (29 gray [Gy] [HFRT] vs. 24 Gy [CRT]). Approximately 14% of the HFRT and 62% of the CRT patients developed primary hypothyroidism within a similar period after irradiation (3.2 years [HFRT] vs. 3.0 years [CRT]). Analysis by cumulative incidence function demonstrated a significant difference in the risk of developing thyroid dysfunction between these two groups of patients (P = 0.02). CONCLUSIONS: The current study findings suggest that the use of HFRT in the treatment of pediatric patients with MB/PNET is associated with a lower risk of these patients developing primary hypothyroidism
PMID: 9264364
ISSN: 0008-543x
CID: 56932

Splicing mutation in CYP21 associated with delayed presentation of salt-wasting congenital adrenal hyperplasia [Case Report]

Kohn B; Day D; Alemzadeh R; Enerio D; Patel SV; Pelczar JV; Speiser PW
Patients with salt-wasting congenital adrenal hyperplasia (SW-CAH) most commonly carry an A-G transition at nucleotide 656 (nt 656 A-->G), causing abnormal splicing of exons 2 and 3 in CYP21, the gene encoding active steroid 21-hydroxylase. Affected infants are severely deficient in cortisol and aldosterone, and usually come to medical attention during the neonatal period. We report on 2 affected boys, homozygous for the nt 656 mutation, who thrived in early infancy, but suffered salt-wasting crises unusually late in infancy, at 3.5 and 5.5 months, respectively. Laboratory studies at presentation showed hyponatremia, hyperkalemia, dehydration, and acidosis; serum aldosterone was low in spite of markedly elevated plasma renin activity. Basal 17-hydroxyprogesterone levels were only moderately elevated, yet the stimulated levels were more typical of severe, classic CAH due to 21-hydroxylase deficiency. Genomic DNA from the patients was analyzed. Southern blot showed no major deletions or rearrangements. CYP21-specific amplification by polymerase chain reaction, coupled with allele-specific hybridization using wild-type and mutant probes at each of 9 sites for recognized disease-causing mutations, revealed a single, homozygous mutation in each patient: nt 656 A-->G. These results were confirmed by sequence analysis. We conclude that the common nt 656 A-->G mutation is sometimes associated with delayed phenotypic expression of SW-CAH. We speculate that variable splicing of the mutant CYP21 may modify the clinical manifestations of this disease
PMID: 7677150
ISSN: 0148-7299
CID: 9045