Kyriakie Sarafoglou

Gonadal function after bone marrow transplantation for acute leukemia during childhood

OBJECTIVE To examine the impact of bone marrow transplantation (BMT), using high-dose chemotherapy and hyperfractionated total body irradiation, on gonadal function in survivors of acute leukemia treated during childhood. STUDY DESIGN We conducted a retrospective study of 33 subjects (17 boys) who underwent a BMT for acute leukemia (acute lymphoblastic leukemia, n = 20; acute myelogenous leukemia, n = 13) at a single institution. All patients were prepubertal at the time of BMT (median age, 7.1 years (3.7 to 11.6 years)); at the time of their last examination the boys were a median of 14 years (10.4 to 17.1 years) of age and the girls were a median of 16.9 years (9.5 to 21.9 years) of age. RESULTS Of 17 boys, 14 (82%) entered puberty spontaneously and 13 demonstrated age-appropriate plasma concentrations of testosterone. Two boys (aged 10.5 and 11 years) remain clinically and hormonally prepubertal, and one boy has overt Leydig cell failure requiring androgen replacement therapy. Thirty-six percent of pubertal boys have elevated plasma concentrations of luteinizing hormone and 64% have raised levels of follicle-stimulating hormone. Boys with increased levels of luteinizing hormone were significantly younger at BMT (5.4 +/- 0.8 vs 7.8 +/- 0.8 years; p = 0.024). Of 16 girls, 9 (56%) had spontaneous puberty with onset of menarche at a median age of 13 years (9.5 to 15.8 years). Though six (67%) of these nine girls have had increased plasma concentrations of luteinizing and follicle-stimulating hormones, normalization has occurred in two during a period of 4 to 7 years. The remaining seven subjects required hormone replacement because of clinical and biochemical evidence of ovarian failure. One of these subjects has recovered ovarian function after 5 1/2 years. Female patients with ovarian failure were significantly older at BMT compared with female patients with spontaneous puberty/menarche (8.6 +/- 23 years vs 6.1 +/- 1.8; p = 0.03). CONCLUSION Our results indicate that most prepubertal boys undergoing BMT with chemotherapy and hyperfractionated total body irradiation can expect to enter and progress normally through puberty. For prepubertal girls treated with these regimens, at least 50% retain adequate ovarian function to enter puberty and menstruate regularly.

Comparison of One-Tier and Two-Tier Newborn Screening Metrics for Congenital Adrenal Hyperplasia

BACKGROUND: Newborn screening (NBS) for the classic forms of congenital adrenal hyperplasia (CAH) is mandated in all states in the United States. Compared with other NBS disorders, the false-positive rate (FPR) of CAH screening remains high and has not been significantly improved by adjusting 17α-hydroxyprogesterone cutoff values for birth weight and/or gestational age. Minnesota was the first state to initiate, and only 1 of 4 states currently performing, second-tier steroid profiling for CAH. False-negative rates (FNRs) for CAH are not well known. METHODS: This is a population-based study of all Minnesota infants (769 834) born 1999–2009, grouped by screening protocol (one-tier with repeat screen, January 1999 to May 2004; two-tier with second-tier steroid profiling, June 2004 to December 2009). FPR, FNR, and positive predictive value (PPV) were calculated per infant, rather than per sample, and compared between protocols. RESULTS: Overall, 15 false-negatives (4 salt-wasting, 11 simple-virilizing) and 45 true-positives were identified from 1999 to 2009. With two-tier screening, FNR was 32%, FPR increased to 0.065%, and PPV decreased to 8%, but these changes were not statistically significant. Second-tier steroid profiling obviated repeat screens of borderline results (355 per year average). CONCLUSIONS: In comparing the 2 screening protocols, the FPR of CAH NBS remains high, the PPV remains low, and false-negatives occur more frequently than has been reported. Physicians should be cautioned that a negative NBS does not necessarily rule out classic CAH; therefore, any patient for whom there is clinical concern for CAH should receive immediate diagnostic testing.

Application of Ultrasound for Bone Age Estimation in Clinical Practice

OBJECTIVE To assess the validity of bone age assessment by ultrasonography (US). STUDY DESIGN Wrist US was performed on children (n = 100) undergoing radiographic bone age and compared with bone age estimation by a radiologist in the clinic and by endocrinologists under blinded conditions with Greulich and Pyle (GP) and Tanner and Whitehouse (TW3) methods. RESULTS The strongest correlation (r(2)) was seen in the radiographic bone age assessment between the 2 endocrinologists using the GP method (96.7%). The poorest correlation was seen when comparing radiographic methods to US of either wrist (74.6% to 82.6%). When bone age correlations were divided into normal, delayed or advanced, the highest correlation between the radiographic and US methods was found in the normal bone age group (80.9% to 86.1%) with weaker correlations for the delayed bone age group (77.1% to 86.9%) and the advanced bone age group (62.2% to 81.1%). US tended to overread delayed bone age and underread advanced bone age. US had poor positive and negative predictive value for identification of a normal or delayed bone age. The negative predictive value of US was 91% for an advanced bone age. CONCLUSIONS On the basis of our data, US assessment should not yet be considered a valid replacement for radiographic bone age determination.

Siblings With Mitochondrial Acetoacetyl-CoA Thiolase Deficiency Not Identified by Newborn Screening

Screened for by all state newborn screening (NBS) programs in the United States, mitochondrial acetoacetyl-coenzyme A thiolase (T2), or β-ketothiolase, deficiency is a rare autosomal recessive disorder that causes ketoacidosis and hypoglycemia/hyperglycemia. Outcomes vary from normal development to severe cognitive impairment or even death after an acute episode of ketoacidosis. The classical biochemical profile of T2 deficiency is a result of null mutations in both alleles of the ACAT1 gene and consists of persistently increased urinary excretion of ketones, characteristic organic acids, and tiglylglycine as well as abnormal blood or plasma acylcarnitine profiles in acute and stable conditions. Early diagnosis and aggressive management can prevent further episodes of ketoacidosis and lead to normal development. We report the cases of 3 children, all subsequently found to have mutations predicted to be associated with no residual T2 enzymatic activity, but only 1 was identified by NBS in Minnesota since 2001. To our knowledge, this is the first description of compound heterozygotes for null mutations associated with no enzymatic activity exhibiting normal urinary organic acid, blood, and plasma acylcarnitine profiles when clinically well, thereby explaining the false-negative NBS results. We suggest that T2 deficiency may be underrecognized, because the incidence of T2 deficiency in Minnesota, on the basis of these 3 cases, is 1 in 232 000, higher than the reported <1 in 1 million incidence. Our cases emphasize that T2 deficiency must be considered in patients who present with ketoacidosis disproportionately severe to the triggering illness despite normal NBS results or nonspecific biochemical findings in blood and urine during asymptomatic periods.

Cases of congenital adrenal hyperplasia missed by newborn screening in Minnesota

新生兒體內因缺乏21-羥化酵素(21α-hydroxylase)導致血中的 17-hydroxyprogesterone(17-OHP)濃度升高,是新生兒篩檢中鑑別先天腎上腺 增生症(CAH)的重要指標。研究基礎為明尼蘇達州自1991/1至2010/12的新生兒篩 檢共838 241例,採集新生兒出生後24-48小時篩檢血片,以時差式螢光免疫分析 法(time-resolved fluoroimmumoassay)測血片中17-OHP數值。研究方法是由明 尼蘇達州衛生部門與三家兒科內分泌中心共同合作整理新生兒篩檢結果呈偽陰 性的病例,分析包括基因檢測,血清中17-OHP數值,臨床及生化表徵。 結果: 在篩檢期間,有52例確診為典型CAH,15例典型CAH包括6例男生和9例女生 (5例salt-wasting和10例simple virilizing 型)第一次篩檢結果正常,偽陰性 率至少為22.4%。造成偽陰性結果的原因不明,可能在於17-OHP增加的時間點較 晚和/或篩檢的敏感度有關。 結論: 即使新生兒篩檢陰性也不能完全排除CAH的可能性,偽陰性結果反而會誤 導並延遲診斷。因此觀察新生兒性別特徵非常重要,尤其是女嬰性別特徵不明 時,更應該加以注意。另外,新生兒篩檢系統應加強教育臨床醫師篩檢偽陰性的 概念,對潛在的偽陰性病人加以適當的臨床關注,以便即時診斷。

SRY GENE EXPRESSION IN THE OVOTESTES OF XX TRUE HERMAPHRODITES

PURPOSE The pathogenesis of 46 XX true hermaphroditism is uncertain and the role of the SRY gene in ovotestis development has not been thoroughly evaluated. We ascertained the presence of the SRY gene and SRY protein in the ovotestis. MATERIALS AND METHODS We evaluated 8 ovotestes by cytogenetic analysis of fibroblast cell culture and analysis of gonadal tissue by polymerase chain reaction to detect the SRY gene and by immunohistochemistry with a monoclonal antibody to human recombinant SRY protein. RESULTS Fibroblast culture of the ovotestes demonstrated a 46XX karyotype. By polymerase chain reaction all 8 ovotestes demonstrated the SRY gene at low levels. By immunohistochemistry SRY protein was detected in all ovotestes, predominantly in Sertoli and germ cells. CONCLUSIONS The SRY gene has a role in ovotestis genesis. Mosaicism with a Y bearing cell line in the gonad is a possible explanation and further study is warranted.

Lesch-Nyhan Variant Syndrome: Variable Presentation in 3 Affected Family Members

BACKGROUND Lesch-Nyhan disease is an inborn error of purine metabolism that results from deficiency of the activity of hypoxanthine phosphoribosyltransferase (HPRT). The heterogeneity of clinical phenotypes seen in HPRT deficiency corresponds to an inverse relationship between HPRT enzyme activity and clinical severity. With rare exception, each mutation produces a stereotypical pattern of clinical disease; onset of neurologic symptoms occurs during infancy and is thought to be nonprogressive. OBJECTIVE To document a family in which a single HPRT gene mutation has led to 3 different clinical and enzymatic phenotypes. DESIGN Case report. Settings A university-based outpatient metabolic clinic and a biochemical genetics laboratory. Patients Three males (2 infants and their grandfather) from the same family with Lesch-Nyhan variant, including one of the oldest patients with Lesch-Nyhan variant at diagnosis (65 years). MAIN OUTCOME MEASURES Clinical and biochemical observations. RESULTS Sequencing of 5 family members revealed a novel mutation c.550G>T in exon 7 of the HPRT gene. The considerably variable clinical phenotype corresponded with the variable enzymatic activity in the 3 males, with the grandfather being the most severely affected. CONCLUSIONS The different phenotypes encountered in the enzymatic analysis of cultured fibroblasts from a single mutation in the same family is unprecedented. The significant decrease in the grandfathers HPRT enzymatic activity compared with that of his grandchildren could be a function of the Hayflick Limit Theory of cell senescence.

Comparison of multiple steroid concentrations in serum and dried blood spots throughout the day of patients with congenital adrenal hyperplasia

Background/Aim: Periodic measurement of plasma concentrations of cortisol precursors on a clinic visit may be of limited value in patients with congenital adrenal hyperplasia because it does not reflect a patient’s circadian patterns of adrenal steroid secretion. Steroid profiling in dried blood spots (DBS) may allow for more frequent and sensitive monitoring. Methods: We compared the agreement between 17α-hydroxyprogesterone (17-OHP) and androstenedione (D4A) levels determined from DBS samples and concurrently collected serum samples. Blood was drawn from 9 congenital adrenal hyperplasia patients every 4 h over a 24-hour period. Serum and DBS steroid levels were measured by liquid chromatography tandem mass spectrometry. Results: DBS determinations of 17-OHP overestimated corresponding serum levels (mean difference 1.67 ng/ml), and underestimated D4A serum levels (mean difference 0.84 ng/ml). However, the DBS assay yielded excellent agreement (97%) with serum 17-OHP, but did considerably poorer for D4A (31%). Conclusions: Our results indicate an excellent agreement between DBS and serum 17-OHP measurements to identify the peaks and troughs associated with an individual’s circadian pattern. Larger-scale studies are required to evaluate the utility of DBS for home monitoring and to determine if more frequent monitoring leads to improved clinical outcomes.

Pubertal development in ALG6 deficiency (congenital disorder of glycosylation type Ic)

Information on the hypothalamic pituitary ovarian axis in congenital disorders of glycosylation (CDG) females is scarce. Varying hormonal profiles and degrees of virilization in CDG females suggest a spectrum of yet unidentified mechanisms affected by impaired N-glycosylation. We describe an ALG6D woman who completed puberty with normal gonadotropins and testosterone levels, no virilization, and regular menses. Hormonal follow-up of CDG females is necessary to improve our understanding of the role of glycosylation in pubertal development.

Molecular testing in congenital adrenal hyperplasia due to 21α‐hydroxylase deficiency in the era of newborn screening

Sarafoglou K, Lorentz CP, Otten N, Oetting WS, Grebe SKG. Molecular testing in congenital adrenal hyperplasia due to 21α‐hydroxylase deficiency in the era of newborn screening.