Exploring metabolic alterations in PYCR2 deficiency: Unveiling pathways and clinical presentations of hypomyelinating leukodystrophy 10

Proline-5-carboxylate reductase 2, encoded by PYCR2 gene, is an enzyme that catalyzes the last step of proline synthesis from pyrroline-5-carboxylate synthetase to proline. PYCR2 gene defect causes hypomyelinating leukodystrophy 10. Up until now, to our knowledge around 38 patients with PYCR2 defect have been reported. Herein, we describe clinical, neuroradiological, biochemical findings, and metabolomic profiling of three new genetically related cases of PYCR2 defects from a large family. Cerebrospinal fluid (CSF) amino acid levels were measured and untargeted metabolomic profiling of plasma and CSF were conducted and evaluated together with the clinical findings in the patients. While plasma and CSF proline levels were found to be totally normal, untargeted metabolomic profiling revealed mild increases of glutamate, alpha-ketoglutarate, and l-glutamate semialdehyde and marked increases of inosine and xanthine. Our findings and all the previous reports suggest that proline auxotrophy is not the central disease mechanism. Untargeted metabolomics point to mild changes in proline pathway and also in purine/pyrimidine pathway.

Cardiovascular Risk Factors in Adolescents with Type 1 Diabetes: Prevalence and Gender Differences

Objective

Cardiovascular diseases (CVD) are the most important cause of morbidity and mortality in patients with type 1 diabetes (T1D). Children with T1D have a similar or higher prevalence of being overweight (OW) or obese (Ob) compared to healthy peers. The aim of this study was to determine the prevalence of CVD risk factors in children and adolescents with T1D and the impact of obesity and sex differences on these factors.

Methods

Data of patients aged 10-21 years and who had been using intensive insulin therapy with a diagnosis of T1D for at least three years were evaluated. Patients were divided into normal weight (NW), OW and Ob groups based on body mass index percentiles. Risk factors for CVD (obesity, dyslipidemia, hypertension) were compared between groups, and impact of gender was also analyzed.

Results

Data of 365 patients (200 girls, 54.8%), were evaluated. Prevalence of OW/Ob was 25.9% and was significantly higher in girls (30.6% vs 20.1%, p<0.001). Rate of hypertension was highest in OW/Ob girls followed by OW/Ob boys, and similar in NW girls and boys (p=0.003). Mean low density lipoprotein cholesterol (LDL-c) and triglyceride (TG) levels were highest in OW/Ob girls, followed by OW/Ob boys, NW girls and NW boys, respectively (p<0.001 and p<0.001, respectively). Mean high density lipoprotein-cholesterol (HDL-c) levels were similar among groups. Rates of high LDL-c and TG were similar between OW/Ob girls and boys and higher than NW girls, followed by NW boys (p<0.001 and p<0.001, respectively). The rate of low HDL-c was similar in OW/Ob girls and boys, and higher than NW girls, followed by NW boys (p<0.001). Overall, girls were 1.9 times more likely than boys to have two or more risk factors for CVD. Factors associated with risk for CVD in multiple logistic regression analyses were being a girl, followed by higher daily insulin dose, higher hemoglobin A1c, and longer duration of diabetes (r=0.856; p<0.001).

Conclusion

In spite of the increased prevalence for obesity in both sexes, the trend for CVD risk factors was greater in Ob girls, followed by Ob boys and NW girls. Girls with T1D are more likely to be OW/Ob and to have CVD risk than boys, highlighting the need for early intervention and additional studies to elucidate the causes.

Long Term Growth Hormone Therapy in a Patient with IGF1R Deletion Accompanied by Delayed Puberty and Central Hypothyroidism

Insulin-like growth factor-1 (IGF-1) is the main driver of growth during prenatal life and acts through insulin-like growth factor 1 receptor (IGF1R). Patients with IGF1R defects exhibit variable phenotypic features. A 10.9-year-old boy presented with severe short stature, microcephaly, minor dysmorphic features and mild mental retardation. Genetic analysis for IGF1R revealed heterozygous deletion of the complete IGF1R. At the age of 12.3 years, daily subcutaneous rhGH was started and continued for a total of 5.7 years in two courses with improvement of height velocity as well as final height. Puberty was delayed and eventually he could not develop full puberty suggesting partial hypogonadotropic hypogonadism. Hypothyroidism initially developed during rhGH therapy. However, low T4 levels sustained after cessation of rhGH therapy thus central hypothyroidism is a likely diagnosis. rhGH has partial effect for induction of growth in cases with IGF1R defects. However, long-term treatment with an early onset may have more beneficial effects. In addition, patients with IGF1R defects should be followed for delayed puberty-hypogonadism, and hypothyroidism.

Basal Serum Thyroxine Level should Guide Initial Thyroxine Replacement Dose in Neonates with Congenital Hypothyroidism

OBJECTIVE

Initial high-dose sodium levothyroxine (Na-LT₄) (10-15 μg/kg/day) replacement for primary congenital hypothyroidism (CH) is recommended in guidelines. However, high-dose Na-LT₄ risks iatrogenic hyperthyroidism. The aim of this study was to investigate the normalizing effect of varying initial doses of Na-LT₄ on serum thyroid hormone levels.

METHODS

Fifty-two patients were analyzed retrospectively. The patients were classified into mild (27/51.9%), moderate (11/21.1%) and severe (14/26.9%) CH, based on initial free thyroxine (fT₄) levels. Time taken to achieve target hormone levels was compared within groups.

RESULTS

Initial mean Na-LT₄ doses for mild, moderate and severe disease were 6.9±3.3, 9.4±2.2 and 10.2±2 μg/kg/day. Serum fT₄ levels reached the upper half of normal range (>1.32 ng/dL) in a median of 16, 13 and 16 days in patients with mild, moderate and severe CH with the mean time from initial treatment to first control visit of 14.8±6 days (range 1-36). There was no significant difference in terms of time to achieve target fT₄ hormone levels according to disease severity (p=0.478). Seven (25.9%), eight (72.7%) and eight (57.1%) patients experienced hyperthyroxinemia (serum fT₄ >1.94 ng/dL) in the mild, moderate, and severe CH groups at the first visit, respectively (p=0.016).

CONCLUSION

Not all patients diagnosed with CH require high-dose Na-LT₄. Initial dose of Na-LT₄ may be selected on the basis of pre-treatment thyroid hormone levels. Some patients with moderate and severe CH, experienced iatrogenic hyperthyroxinemia even though the dose was close to the lower limit of the recommended range in guidelines. We suggest that lower initial doses may be appropriate with closer follow-up within the first week.

Gender-related differences in etiology of organic central precocious puberty

BACKGROUND

Central precocious puberty (CPP) is idiopathic in 90% of girls and 60% of boys, while some cases are caused by lesions of central nervous system (CNS), a condition often referred to as organic CPP. We aimed to analyze the etiology of organic CPP in a large cohort of girls and boys and determine gender-related differences.

METHODS

Medical files of 256 girls and 120 boys diagnosed and treated for CPP in a single center in the last two decades were reviewed. Patients were classified into four groups with respect to previous history and MRI findings: (1) previously established CNS pathology at the time of diagnosis, (2) novel CNS pathology previously asymptomatic, (3) incidentalomas considered to be unrelated to CPP, and (4) completely normal MRI. Group 1 and 2 were considered as organic CPP whereas group 3 and 4 were considered as idiopathic CPP.

RESULTS

Prevalence of CNS pathology was significantly higher in boys than girls (21.7% vs 6.2%). Previous CNS pathologies such as developmental anomaly of CNS, parenchymal injury, necrotic lesions and hydrocephalus were present in 3.5% of girls and 8.3% of boys. Prevalence of novel CNS pathology as determined by imaging among neurologically asymptomatic patients was 2.8% in girls and 14.5% in boys. The most common novel CNS pathologies in boys were hamartomas (5%) and suprasellar arachnoid cysts (3.3%); which were significantly lower in girls (0.8 and 0.8% respectively). Onset of organic CPP was before six years in girls, and seven years in boys.

CONCLUSIONS

Organic CPP was 3.5 times more common in boys compared to girls. It is possible to detect an underlying CNS pathology in one out of every five boys with CPP. Frequency and distribution of organic etiology also differ between girls and boys, hypothalamic hamartomas and suprasellar arachnoid cysts being more common in boys than girls. The likelihood of novel intracranial pathology associated with CPP is quite low in girls with an onset after six years of age and in boys with an onset after seven years of age.

Diazoxide-Induced Neutropenia and Long-Term Follow-up in a Patient with Hyperinsulinemia-Hyperammonemia due to GLUD1 Mutation

Hyperinsulinism/hyperammonemia (HI/HA) syndrome is caused by activating mutations in GLUD1 gene, and causes fasting as well as protein sensitive symptomatic hypoglycemia, in addition to persistently elevated plasma ammonia levels. First-line treatment is diazoxide, and most patients respond well to this agent, however side effects may be observed. The most frequent side effect of diazoxide is fluid retention and hypertrichosis, while hyperuricemia and hematologic side effects are observed less often. Herein, we report a case who had a heterozygous mutation of GLUD1 gene and who developed diazoxide related neutropenia 8 years after the start of treatment. On follow-up, leucopenia and mild neutropenia persisted and the treatment was changed to somatostatin analogues. However, she developed persistent severe symptomatic hypoglycemia and required diazoxide retreatment. A lower dose of diazoxide (6 mg/kg/day) successfully controlled hypoglycemia and cell counts increased even though they were not normalized. Neutropenia in current case presented after a long period of time of diazoxide use and this period is the longest defined in the literature. Long-term endocrine and hematologic follow-up of this patient up to 18 years old will also be presented.

Urinary bisphenol A levels in prepubertal children with exogenous obesity according to presence of metabolic syndrome

OBJECTIVES

Recent studies have shown a potential link between chronic exposure to Bisphenol A (BPA) and exogenous obesity, the prevalence of which has been increasing dramatically in all age groups and particularly among children in the last decades. In this study, we aimed at comparing BPA exposure levels between controls and otherwise healthy, drug-naive, pre-pubertal children having exogenous obesity with/without metabolic syndrome.

METHODS

A total of 63 pre-pubertal children with exogenous obesity whom 27 of them having metabolic syndrome attending Hacettepe University Ihsan Dogramaci Children's Hospital were included in this study. The control group consisted of 34 age- and sex-matched healthy children with no significant underlying medical conditions. Urinary BPA levels were measured using LC-MS/MS (high-performance liquid chromatography coupled with tandem mass spectrometry) methodology.

RESULTS

Urinary BPA levels among obese children were significantly higher than those of the control group (median: 22.9 μg/g-creatinine and 6.9 μg/g-creatinine, respectively; p=0.0001). When adjusted with generalized linear models for age, gender and z scores of body mass index, obese children having metabolic syndrome had significantly higher urinary BPA levels than obese children without metabolic syndrome and both obese groups had considerably elevated levels of urinary BPA than the controls (estimated marginal mean ± standard error: 42.3 ± 7.4 μg/g-creatinine, 22.6 ± 3.5 μg/g-creatinine and 12.1 ± 2.5 μg/g-creatinine, respectively, p=0.0001).

CONCLUSIONS

This study shows much higher BPA exposure among obese children with metabolic syndrome during the prepubertal period.

Genetic IGF1R defects: new cases expand the spectrum of clinical features

PURPOSE

We aimed to identify the phenotypic variability of IGF1R defects in a cohort of short children with normal GH secretion gathered through the last decade.

PATIENTS AND METHODS

Fifty children (25 girls) with short stature and a basal/stimulated growth hormone (GH) over 10 ng/ml having either a low birth weight or microcephaly were enrolled. MLPA and then Sanger sequence analysis were performed to detect IGF1R defects. The auxological and metabolic evaluation were carried out in index cases and their first degree family members whenever available.

RESULTS

A total of seven (14%) IGF1R defects were detected. Two IGF1R deletions and five heterozygous variants (one frameshift, four missense) were identified. Three (likely) pathogenic, one VUS and one likely benign were classified by using ACMG. All children with IGF1R defects had a height < - 2.5SDS, birth weight < - 1.4SDS, and head circumference < - 1.36SDS. IGF-1 ranged from - 2.44 to 2.13 SDS. One child with a 15q terminal deletion had a normal phenotype and intelligence, whereas low IQ is a finding in a case with missense variant. Two parents who carried IGF1R mutations had diabetes mellitus, hypertension and hyperlipidemia, one of whom also had hypergonadotropic hypogonadism.

CONCLUSION

We found a deletion or variant in IGF1R in 14% of short children. Birth weight, head circumference, intelligence, dysmorphic features, IGF-1 levels and even height are not consistent among patients. Additionally, metabolic and gonadal complications may appear during adulthood, suggesting that patients should be followed into adulthood to monitor for these late complications.

Clinical and Molecular Analysis in 2 Families With Novel Compound Heterozygous SBP2 (SECISBP2) Mutations

CONTEXT

Selenocysteine insertion sequence binding protein 2 (SECISBP2, SBP2) is an essential factor for selenoprotein synthesis. Individuals with SBP2 defects have characteristic thyroid function test (TFT) abnormalities resulting from deficiencies in the selenoenzymes deiodinases. Eight families with recessive SBP2 gene mutations have been reported to date. We report 2 families with inherited defect in thyroid hormone metabolism caused by 4 novel compound heterozygous mutations in the SBP2 gene.

CASE DESCRIPTIONS

Probands 1 and 2 presented with growth and developmental delay. Both had characteristic TFT with high T4, low T3, high reverse T3, and normal or slightly elevated TSH. The coding region of the SBP2 gene was sequenced and analysis of in vitro translated wild-type and mutant SBP2 proteins was performed. Sequencing of the SBP2 gene identified novel compound heterozygous mutations resulting in mutant SBP2 proteins E679D and R197* in proband 1, and K682Tfs*2 and Q782* in proband 2. In vitro translation of the missense E679D demonstrated all four isoforms, whereas R197* had only 2 shorter isoforms translated from downstream ATGs, and Q782*, K682Tfs*2 expressed isoforms with truncated C-terminus. Reduction in serum glutathione peroxidase enzymatic activity was also demonstrated in both probands.

CONCLUSIONS

We report 2 additional families with mutations in the SBP2 gene, a rare inherited condition manifesting global selenoprotein deficiencies. Report of additional families with SBP2 deficiency and their evaluation over time is needed to determine the full spectrum of clinical manifestations in SBP2 deficiency and increase our understanding of the role played by SBP2 and selenoproteins in health and disease.

Treatment with Depot Leuprolide Acetate in Girls with Idiopathic Precocious Puberty: What Parameter should be Used in Deciding on the Initial Dose?

OBJECTIVE

Doses of gonadotropin releasing hormone (GnRH) analogues used to treat idiopathic central precocious puberty (iCPP) vary among clinicians. Study aims were to evaluate the efficacy of a monthly 3.75 mg dose of leuprolide acetate (LA) to suppress the hypothalamo-pituitary-gonadal (HPG) axis in girls with iCPP and to determine factors that may have an impact on the supressing dose.

METHODS

Study subjects were 220 girls receiving LA for iCPP. LA was started at a dose of 3.75 mg/28 days. Suppression was assessed using the GnRH test at the third month. To assess clinical suppression signs and symptoms of puberty were also evaluated. The dose of LA was increased to 7.5 mg/28 days in those who had a peak luteinising hormone (LH) ≥2 IU/L and in whom adequate clinical suppression of puberty was absent. Receiver operating characteristic curves were used to determine thresholds for clinical and hormonal factors affecting the suppressing dose of LA. Logistic regression analyses were used to investigate thresholds which might differentiate between those requiring high dose for suppression and those in whom lower dose LA was adequate.

RESULTS

Peak stimulated LH <2 IU/L was achieved in 88.6% with a dose of LA of 3.75 mg (0.11±0.03 mg/kg). Significant variables for differentiating the two doses were body weight (Wt) of 36.2 kg and/or body mass index (BMI)-standard deviation scores (SDS) of 1.64 (p<0.001). Multiple logistic regressions showed that Wt and BMI-SDS values above thresholds indicated requirement of LA at a dose of 7.5 mg/28 days (p<0.001).

CONCLUSION

Monthly injections of 3.75 mg LA is an effective treatment in the majority of girls with iCPP. However, a higher initial dose may be preferred in patients with a Wt ≥36 kg or BMI-SDS ≥1.6 for effective suppression of the HPG axis.

Acquired resistance to pamidronate treated effectively with zoledronate in juvenile Paget's disease

Juvenile Paget's disease (JPD) is a rare autosomal recessive osteopathy. There is still a question about the most effective treatment modality in long-term prognosis. A 9-month-old boy who suffered from bone pain and deformities with a very high alkaline phosphatase level was diagnosed as JPD by radiographic findings. Genetic analysis showed a homozygous large deletion in TNFRSF11B gene encoding osteoprotegerin. Clinical improvement was observed with intravenous pamidronate therapy. However, the effect of drug reduced in time so the annual dose per kilogram body weight was increased after 2 years. Despite this increment, bone fractures developed and bone pain recurred with high-ALP levels, which suggested resistance to pamidronate. Switching to zoledronate resulted a significant improvement in bone findings radiographically and ALP level. Severe hypocalcemia requiring intravenous calcium treatment complicated the first dose of zoledronate, but not recurred thereafter. Intravenous pamidronate therapy is effective in reducing bone pain, improving bone deformities and motor development in infantile onset JPD. However, this effect can be transient. Switching to another bisphosphonate like zoledronate may provide long-term clinical and biochemical improvement as an alternative treatment in case of resistance to pamidronate therapy.

Long-Term Follow-up of a Case with Proprotein Convertase 1/3 Deficiency: Transient Diabetes Mellitus with Intervening Diabetic Ketoacidosis During Growth Hormone Therapy

Proprotein convertase 1/3 (PC1/3) deficiency is a very rare disease characterized by severe intractable diarrhea in the first years of life, followed by obesity and several hormonal deficiencies later. Diabetes mellitus requiring insulin treatment and diabetic ketoacidosis have not been reported in this disorder. We herein present a girl with PC1/3 deficiency who has been followed from birth to 17 years of age. She developed deficiencies of all pituitary hormones over time as well as diabetes mellitus while receiving growth hormone (GH) therapy. She was complicated with diabetic ketoacidosis during dietary management of diabetes mellitus, thus insulin treatment was initiated. Insulin requirement to regulate hyperglycemia was short-lived. Repeat oral glucose tolerance test five years later was normal. The findings of this patient show that diabetes mellitus can develop at any time during follow-up of cases with proportein convertase 1/3 deficiency especially under GH therapy.

Growth Hormone Deficiency in a Child with Neurofibromatosis-Noonan Syndrome

Neurofibromatosis-Noonan syndrome (NFNS) is a distinct entity which shows the features of both NF1 (neurofibromatosis 1) and Noonan syndrome (NS). While growth hormone deficiency (GHD) has been relatively frequently identified in NF1 and NS patients, there is limited experience in NFNS cases. The literature includes only one case report of a NFNS patient having GHD and that report primarily focuses on the dermatological lesions that accompany the syndrome and not on growth hormone (GH) treatment. Here, we present a 13-year-old girl who had clinical features of NFNS with a mutation in the NF1 gene. The case is the first NFNS patient reported in the literature who was diagnosed to have GHD and who received GH treatment until reaching final height. The findings in this patient show that short stature is a feature of NFNS and can be caused by GHD. Patients with NFNS who show poor growth should be evaluated for GHD.

Surgical and clinical strategies in the management of thyroid medullary carcinoma in children with and without ret proto-oncogene mutations

Medullary thyroid carcinoma (MTC) may arise sporadically or in familial manner. We presented sporadic and familial cases with MTC in order to raise awareness on management of such patients. Three medullary thyroid carcinoma (MTC) cases were presented. Case 1 had RET634 mutation; managed with total thyroidectomy (TT) and cervical lymph node dissection (CLND). Case 2 had RET804 mutation; managed with prophylactic TT. Case 3 had thyroid nodule; managed with TT and CLND. Case 1 had micro-carcinomatosis foci, Case 2 had normal thyroid tissue in histopathological examination and Case 3 had medullary thyroid carcinoma with tumor negative surgical borders. Case 1 was re-operated for persisting focus of disease. Follow-up of cases were uneventful. Clinicians and surgeons should be aware of critical timing for surgery and various surgical and clinical strategies in the management of MTC in children.

Hyperthyroidism After Allogeneic Hematopoietic Stem Cell Transplantation: A Report of Four Cases

Hematopoietic stem cell transplantation (HSCT) is the only curative treatment for many hematological disorders, primary immunodeficiencies, and metabolic disorders. Thyroid dysfunction is one of the frequently seen complications of HSCT. However, hyperthyroidism due to Graves' disease, autoimmune thyroiditis, and thyrotoxicosis are rare. Herein, we report a series of 4 patients who were euthyroid before HSCT but developed hyperthyroidism (3 of them developed autoimmune thyroid disease) after transplantation.

Severe Undervirilisation in a 46,XY Case Due to a Novel Mutation in HSD17B3 Gene

17-β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) is an important enzyme involved in the final steps of androgen synthesis and is required for the development of normal male external genitalia. 46,XY individuals with deficiency of this enzyme present a wide clinical spectrum from a female appearance of the external genitalia through ambiguous genitalia to a predominantly male genitalia with micropenis or hypospadias. This paper reports a one-year-old 46,XY patient with 17β-HSD3 deficiency who presented with female external genitalia and bilaterally palpable gonads in the inguinal region. The low T/Δ4 ratio after human chorionic gonadotropin (hCG) stimulation suggested 17β-HSD3 deficiency. A homozygous mutation, c.761_762delAG, was determined at the intron 9/exon 10 splice site of the HSD17B3 gene. To the best of our knowledge, this mutation has not been reported thus far, but its localization and type would imply a complete disruption of the 17β-HSD3 which may explain the phenotype of our patient.

A novel mutation in leukocyte adhesion deficiency type II/CDGIIc

Leukocyte adhesion deficiencies (LAD) are autosomal recessive immunodeficiency syndromes characterized by severe and recurrent bacterial infections, impaired wound healing and leukocytosis. Block in different steps in the leukocyte adhesion cascade causes different types of leukocyte adhesion deficiencies, LAD type I, II and III. In LAD type II, the rolling phase of the leukocyte adhesion cascade is affected due to mutations in the specific fucose transporter GFTP (GDP fucose transporter), causing defect in the biosynthesis of selectin ligands on leukocytes. Thus this syndrome is also called congenital disorder of glycosylation IIc (CGDIIc). LAD II/CGDIIc is very rare and has been diagnosed in nine children to date. Fever, leukocytosis, typical dysmorphic features, growth, psychomotor retardation and the Bombay blood group, are characteristic findings in patients. Here, we describe two Turkish siblings with a novel mutation in GFTP. They both have the characteristic features of the syndrome. The older sibling died of severe bacterial pneumonia at the age of 3 years. The younger sibling, diagnosed at the age of 3 months, responded to high dose oral fucose supplementation. Secundum atrial septal defect which was not described in previously reported patients, but present in both of our patients, may primarily related to the defect in fucosylation.

Need for comprehensive hormonal workup in the management of adrenocortical tumors in children

OBJECTIVE

Clinical findings do not reflect the excess hormonal status in adrenocortical tumors (ACTs) in children. Identification of abnormal hormone secretion may help provide the tumor marker and delineate those patients with a risk of adrenal suppression following tumor removal. To analyze the impact of complete hormonal assessment regardless of the clinical presentation in hormone-secreting ACTs in childhood.

METHODS

Association of hormonal workup at diagnosis with the clinical findings and frequency of adrenal suppression postoperatively were analyzed in 18 children with ACT.

RESULTS

Seventeen of the 18 patients had functional ACT. Clinical findings suggested isolated virilization and isolated Cushing's syndrome in 38.8% and 17.6% of patients, respectively. Hormonal workup revealed a frequency of 83.3% for hyperandrogenism. The majority of the tumors (50%) had mixed type hormonal secretion. Hypercortisolism existed in 28.5% of children with isolated virilization and hyperandrogenism was found in 2/3 of children with isolated Cushing's syndrome. Various androgens other than dehydroepiandrosterone sulfate were also determined to be high in hyperandrogenism. Increased testosterone was a highly prevalent tumor marker. Nine patients (3 with no signs of hypercortisolism) had adrenal suppression following tumor removal which lasted 1-24 months.

CONCLUSION

Complete hormonal workup showed the predominance of mixed hormone-secreting type of tumor in the patients who lacked the appropriate clinical findings and also showed that patients lacking signs of Cushing's syndrome could have postoperative adrenal suppression. Clinical findings may not reflect the abnormal hormone secretion in all cases and tumor markers as well as risk of postoperative adrenal suppression can best be determined by complete hormonal evaluation at the time of diagnosis.

N-acetylcycsteine attenuates the deleterious effects of radiation therapy on inci-sional wound healing in rats

BACKGROUND

During preoperative radiotherapy, effective doses of ionizing radiation occasionally cause wound complications after subsequent surgery. This study was designed to determine the effects of intraperitoneally or orally administered N-acetylcysteine (NAC) on anastomotic healing of irradiated rats.

MATERIAL & METHODS

Forty Wistar albino rats were randomized into four groups containing 10 rats each. A 3 cm long surgical full-thickness midline laparotomy was performed to all groups (Groups 1-4). Group 1 was designed as a control group without radiation therapy and NAC treatment. Groups 2, 3 and 4 received a single abdominal dose of 10 Gy irradiation before laparotomy and groups 3 and 4 received oral and intraperitoneal NAC, respectively.

RESULTS

Group comparisons demonstrated that breaking strength was significantly higher in NAC treated rats. A statistically significant difference was determined in terms of superoxide dismutase (SOD), malondealdehyde (MDA) and glutation (GSH) values between groups (p<0.001). Nevertheless, advanced oxidation protein products (AOPP) levels were found to be similar between groups (p=0.163). Serum GSH and SOD levels were significantly higher in groups 3 and 4 when compared to group 2 (p < 0.05). Similarly, there was a significant increase in serum MDA concentration, predicting lipid peroxidation, in group 2 when compared to groups 1, 3 and 4 (p < 0.05). There was not a significant difference between Groups 3 and 4 regarding GSH, MDA, SOD, and AOPP levels. Histopathological analysis revealed that NAC administration, either orally or intraperitoneally, leads to a better incisional healing in terms of inflammation, granulation, collagen deposition, reepithelization and neovascularization.

CONCLUSION

The present study supports the hypothesis that NAC administration alleviates the negative effects of radiotherapy on incisional wound healing by means of reducing oxidative stress markers and improving histologic parameters independent of the route of administration.

Efficacy and safety of pneumatic trabeculoplasty versus timolol added to latanoprost in primary open angle glaucoma

BACKGROUND

To compare the safety and short-term additive hypotensive effect of pneumatic trabeculoplasty (PNT) versus timolol among patients receiving topical latanoprost for primary open angle glaucoma (POAG).

PATIENTS AND METHODS

This study prospectively evaluated 30 eyes of 30 patients with POAG receiving latanoprost monotherapy. We randomly assigned 15 eyes to PNT plus latanoprost (Group A), and 15 eyes to latanoprost/timolol fixed combination therapy (Group B). PNT treatment was performed at days 0, 7, and 90. Follow-up visits occurred at day 1, week 1, and months 1 and 3.

RESULTS

Compared to baseline values, both treatments significantly lowered IOP (p ≤ 0.001).The mean IOP for Group A was 21.13 ± 1.6 mmHg at baseline and 18.7 ± 1.5 mmHg at three months (p ≤ 0.001). For Group B, mean IOP was 20.8 ± 1.9 mmHg at baseline and 18.9 ± 0.8 mmHg at three months (p ≤ 0.001). Transient conjunctival hyperaemia, the only adverse effect occurring after PNT, was observed in all patients in Group A.

CONCLUSION

The additive IOP-lowering effect of PNT was similar to timolol in patients with POAG receiving latanoprost.

Carotid intima media thickness in adolescents with increased risk for atherosclerosis

In this study, we aimed to analyze early-onset atherosclerotic changes in adolescents with risk of cardiovascular disease in comparison to healthy controls using carotid intima media thickness (CIMT), homocysteine and markers of endothelial function as indicators. Children aged 10 years or older, all pubertal, with type 1 diabetes mellitus (T1DM), obesity, or obesity with glucose intolerance and age- and sex-matched healthy controls were included in the study. Endothelial markers (von Willebrand factor [vWF], tissue plasminogen activator [tPA], plasminogen activator inhibitor [PAI]-1), CIMT, homocysteine, folic acid, and vitamin B12 levels were measured in all subjects. Mean CIMT of the obese subjects were significantly higher than that of lean diabetic children and healthy controls (p=0.024). There was an independent relationship between CIMT and homocysteine level (b=0.76, p<0.0001). Further, homocysteine was negatively correlated with vitamin B12 (r=-0.20, p<0.001) and folic acid (r=-0.44, p<0.001). Homocysteine is an independent risk factor for early atherosclerosis in adolescents, which may be controlled by supplementation with vitamin B12 and folic acid.

Variations in tumor marker levels in metastatic breast cancer patients according to tumor subtypes

PURPOSE

To investigate whether serum CA 15-3 and CEA levels show differences among subgroups of breast cancer patients at the time of diagnosis of early-stage disease and at disease relapse.

METHODS

Patients with metastatic breast cancer diagnosed from 2000 to 2010 were retrospectively analyzed. Data were obtained from medical charts. CA 15-3 and CEA levels of patients with metastatic disease at the time of diagnosis or who relapsed during follow-up were evaluated. Four different breast cancer subtypes were defined: estrogen receptor (ER) and/or progesterone receptor (PR) positive and HER-2 negative (luminal A), ER and/or PR positive and HER-2 positive (luminal B), ER and PR negative and HER-2 positive (HER-2 overexpressing) and triple negative (ER, PR and HER-2 negative). Fifty-eight (13.7%) of the patients were metastatic at the time of diagnosis.

RESULTS

423 metastatic breast cancer patients were included. Of the patients, 232 (54.8%) had luminal A disease, 70 (16.5%) luminal B, 53 (12.5%) HER-2 overexpressing, and 68 (16.1%) triple negative disease. Preoperative CA 15-3 levels were raised in 48.1% of the luminal A group, in 42.8% of the luminal B group, in 26.0% of the HER-2 overexpressing group, and in 33.3% of the triple negative group. CA 15-3 levels after relapse were raised in 44.5% of the luminal A group, in 33.3% of the luminal B, in 28.9% of the HER-2 overexpressing, and in 38.8% of the triple negative group. Preoperative CEA levels were elevated in 44.3% of the luminal A group, in 28.5% of the luminal B, in 43.4% of the HER-2 overexpressing, and in 14.3% of the triple negative group. CEA levels after relapse were raised in 60.8%, 54.7%, 51.1%, and 36.0% of the patients in the 4 subgroups, respectively.

CONCLUSION

This study showed that there are differences between the breast cancer subgroups in terms of tumor marker levels in metastatic breast cancer patients. Tumor marker elevation was lower in the triple negative group as compared to the luminal groups. Monitoring CEA levels in luminal A group may be beneficial in determining early relapses. However, this retrospective study requires further prospective confirmative cohort studies.

Thyroid hormone resistance: a novel mutation in thyroid hormone receptor beta (THRB) gene - case report

Thyroid hormone resistance (THR) is a dominantly inherited syndrome characterized by reduced sensitivity to thyroid hormones. It is usually caused by mutations in the thyroid hormone receptor beta (THRB) gene. In the present report, we describe the clinical and laboratory characteristics and genetic analysis of patients with a novel THRB gene mutation. The index patient had been misdiagnosed as hyperthyroidism and treated with antithyroid drugs since eight days of age. Thyroid hormone results showed that thyrotropin (thyroid-stimulating hormone, TSH) was never suppressed despite elevated thyroid hormone levels, and there was no symptom suggesting hyperthyroidism. A heterozygous mutation at codon 350 located in exon 9 of the THRB gene was detected in all the affected members of the family. It is important to consider thyroid hormone levels in association with TSH levels to prevent inappropriate treatment and the potential complications, such as clinical hypothyroidism or an increase in goiter size.

Frequency of mutations in PROP-1 gene in Turkish children with combined pituitary hormone deficiency

Mutations in the prophet of Pit-1 (PROP-1) gene are responsible for most of the cases of combined pituitary hormone deficiencies (CPHD). We performed this study to determine the prevalence of PROP-1 mutations in a group of Turkish children with CPHD. Fifty-three children with the diagnosis of CPHD were included in this study. Clinical data were obtained from medical files, and hormonal evaluation and genetic screening for PROP-1 mutations were performed. A homozygous S109X mutation was found in the second exon in two brothers, and they had growth hormone (GH) and thyroid-stimulating hormone (TSH) deficiencies and normal prolactin levels. In the third exon of the PROP-1 gene, a heterozygous A142T polymorphism was found in 14 patients and a homozygous A142T polymorphism was found in 3 patients. In the first exon, a homozygous A9A polymorphism was found in 7 patients and a heterozygous A9A polymorphism was found in 31 patients. We assumed that mutations in the PROP-1 gene in cases with CPHD were expected to be more prevalent in our population due to consanguinity, but it was found that these mutations were far less than expected and that it was rare in non-familial cases.

Hypophosphatasia presenting with pyridoxine-responsive seizures, hypercalcemia, and pseudotumor cerebri: case report

Hypophosphatasia (HPP) is an inborn error of metabolism characterized by defective bone mineralization caused by a deficiency in alkaline phosphatase (ALP) activity due to mutations in the tissue-nonspecific ALP (TNALP) gene. The clinical expression of the disease is variable. Six forms of HPP are identified according to age at presentation and clinical features. Patients with the infantile form are normal at birth. First symptoms appear within the first 6 months of life. Along with skeletal findings, HPP patients may present with hypercalcemia, seizures, pseudotumor cerebri, and pulmonary insufficiency. Seizures in HPP are refractory to conventional antiepileptic drugs, but are responsive to pyridoxine. Herein, we report a case of HPP who presented with pyridoxine-responsive seizures in the early neonatal period and was found to have hypercalcemia, skeletal demineralization and increased intracranial pressure.

Is basal serum 17-OH progesterone a reliable parameter to predict nonclassical congenital adrenal hyperplasia in premature adrenarche?

To determine the critical features for the diagnosis of nonclassical 21 hydroxylase deficiency (NC210HD) without performing adrenocorticotropic hormone (ACTH) test, we studied 186 cases with premature adrenarche. Clinical and laboratory features as well as basal 17-hydroxyprogesterone (17-OHP) were analyzed to determine factors important for differentiating NC21OHD. Overall, 6 patients (3.2%) had ACTH-stimulated 17-OHP > 10 ng/ml. A cutoff level of 2 ng/ml for basal 17-OHP was 66.7% sensitive and 78% specific for NC21OHD; however, a cutoff level of 1.55 ng/ml had higher sensitivity (83%) and specificity (70.6%). A cutoff of 1.55 ng/ml would lead to 31% of cases with premature adrenarche having to undergo ACTH test, and only one case would have been missed. That case had a bone age SDS > 2. Three cases out of five with a basal 17-OHP > 5 ng/ml had stimulated 17-OHP < 10 ng/ml. A cutoff of 1.55 ng/ml for basal 17-OHP together with bone SDS > 2 in those with lower basal levels as a guide for carrying out an ACTH test may yield better results in the diagnosis of NC21OHD in the premature adrenarche population. A cutoff of 5 ng/ml for basal 17-OHP should not be used for diagnosis of NC21OHD.

GnRH stimulation test in precocious puberty: single sample is adequate for diagnosis and dose adjustment

OBJECTIVE

Gonadotropin stimulation test is the gold standard to document precocious puberty. However, the test is costly, time-consuming and uncomfortable. The aim of this study was to simplify the intravenous gonadotropin-releasing hormone (GnRH) stimulation test in the diagnosis of precocious puberty and in the assessment of pubertal suppression.

METHODS

Data pertaining to 584 GnRH stimulation tests (314 tests for diagnosis and 270 for assessment of pubertal suppression) were analyzed.

RESULTS

Forty-minute post-injection samples had the greatest frequency of "peaking luteinizing hormone (LH)" (p<0.001) in the diagnostic tests when the cut-off value was taken as 5 IU/L for LH, 40th minute sample was found to have 98% sensitivity and 100% specificity in the diagnosis of precocious puberty, while the sensitivity and specificity of the 20th minute sample was 100% in the assessment of pubertal suppression.

CONCLUSION

LH level at the 40th minute post-injection in the diagnosis of central precocious puberty and at the 20th minute post-injection in the assessment of pubertal suppression is highly sensitive and specific. A single sample at these time points can be used in the diagnosis of early puberty and in the assessment of pubertal suppression.

Anemia and neutropenic fever with high dose diazoxide treatment in a case with hyperinsulinism due to Munchausen by proxy

BACKGROUND

The etiology of hyperinsulinemic hypoglycemia in adolescents is similar to that of adults. Patients resistant to medical treatment may undergo pancreatectomy. Diazoxide is the mainstay of medical treatment. Rarely bone marrow suppression is reported due to diazoxide.

PATIENT

An adolescent with severe hyperinsulinemic hypoglycemia was referred for pancreatectomy after she was treated with high doses of diazoxide, octreotide and glucose. She developed anemia and febrile neutropenia in the course of diazoxide treatment that resolved with cessation of medication. The cause of the hyperinsulinemia proved to be classical Munchausen by proxy.

CONCLUSION

This is the first report of bone marrow suppression involving erythroid series by diazoxide. Follow-up of blood count may be considered in patients on high dosages since anemia may be dose dependent. Munchausen by proxy poses a serious threat to children with significant morbidity and mortality. Awareness and a high index of suspicion in clinical settings with unusual causes are the mainstay for the diagnosis.

Phosphate Solubilization Potentials of Acinetobacter Strains and their Relations with Soil Properties

<p>Phosphate solubilizing bacteria can be used as soil or seed inoculum to increase soil phosphorus (P) availability for agricultural purposes. There is also a possibility of using these microorganisms to biotechnologically dissolve phosphate ores for the production of phosphorus fertilizers. Twenty-one soil samples were collected along a highway in Turkey to isolate phosphate solubilizing bacteria. A total of 20 phosphate solubilizers were isolated from the rhizosphere of wheat and maize grown in the pots, which contained the collected soil samples. The isolates were distributed among the genera, <em>Acinetobacter</em> (7), <em>Pseudomonas</em> (7), <em>Enterobacter</em> (2), <em>Enterococcus</em> (1), <em>Escherichia</em> (1), <em>Photorhabdus</em> (1), and <em>Bacillus</em> (1) as determined by the 16S rDNA gene sequence analysis. Since the <em>Acinetobacter</em> species were most effective in Pikovskaya’s agar, which contained tricalcium phosphate for the sole P-source, they were further experimented for the phosphate solubilization in batch cultures. The mean phosphorus dissolved in 5 day incubation ranged between 167 and 1022 ppm P. The initial pH of 7.8  dropped below 4.7 in six isolates with a gluconic acid production in the concentrations ranging between 27.5 and 37.5 mM. <em>Acinetobacter</em> isolates have some potential as an inoculum both for soil and biotechnological P-solubilization.</p>

Growth hormone deficiency due to traumatic brain injury in a patient with X-linked congenital adrenal hypoplasia

X-linked adrenal hypoplasia congenita (AHC) is characterized by primary adrenal insufficiency and is frequently associated with hypogonadotropic hypogonadism (HH). The production of other pituitary hormones (adrenocorticotropic hormone [ACTH], growth hormone [GH], thyroid-stimulating hormone [TSH], and prolactin [PRL]) is usually normal. Mutations of the DAX-1 gene have been reported in patients with AHC and HH. We present a 13-year-old male patient with AHC caused by a nonsense mutation in the DAX-1 gene who developed GH deficiency following head trauma. He showed signs of adrenal insufficiency at the age of 23 months, and glucocorticoid and mineralocorticoid treatment was started. His parents reported head trauma due to a traffic accident at the age of 21 months. Adrenal computed tomography revealed hypoplasia of the left and agenesis of the right adrenal gland. Decreased growth rate was noted at the age of 12.5 years while receiving hydrocortisone 15 mg/m2/day. His height was 139.9 cm (-1.46 SD), body weight was 54.9 kg, pubic hair was Tanner stage 1, and testis size was 3 ml. His bone age was 7 years. His gonadotropin (follicle-stimulating hormone [FSH], luteinizing hormone [LH]) and testosterone levels were prepubertal. The evaluation of GH/insulin-like growth factor-1 (IGF-1) secretion at the age of 13 years revealed GH deficiency. Pituitary magnetic resonance imaging demonstrated a hypoplastic hypophysis (< 2.5 mm) and a normal infundibulum. GH treatment (0.73 IU/kg/week) was started. This paper reports a patient with genetically confirmed AHC demonstrating GH deficiency possibly due to a previous head trauma. Complete pituitary evaluation should be performed in any child who has survived severe traumatic brain injury.

The relationship between serum adiponectin, tumor necrosis factor-alpha, leptin levels and insulin sensitivity in childhood and adolescent obesity: adiponectin is a marker of metabolic syndrome

OBJECTIVE

This study aimed (a) to investigate the relationship between the degree of obesity and serum adiponectin, tumor necrosis factor (TNF)-α, leptin, insulin levels and the lipid profile; (b) to clarify the relationship between insulin resistance/glucose tolerance and adipocytokine levels; and (c) to investigate the value of adipocytokine levels as a marker of metabolic syndrome (MS).

METHODS

We studied 151 obese children and adolescents (86 boys and 65 girls; mean age was 12.3±2.4 years). We defined obesity as a body-mass index (BMI) z-score more than 2 SD above the mean for age and sex. The control group consisted of 100 children (48 boys, 52 girls, mean age 12.4±2.5 years). Fasting glucose, insulin levels and lipid profiles were measured in all cases and controls after a 12-hour fast. Adiponectin, TNF-α, and leptin levels were measured in the subjects who participated in the adipocytokine branch of the study. An oral glucose tolerance test (OGTT) was also performed in all obese patients. Obese patients were grouped into three subgroups according to their glucose tolerance and insulin sensitivity assessment, and also according to whether they were grouped as MS or not.

RESULTS

Serum levels of total cholesterol, LDL and VLDL cholesterol, log triglyceride, insulin, leptin and TNF-α were higher, whereas HDL and square root adiponectin levels were lower in the obese group when compared with controls. Multiple regression analysis among BMI-z score, LDL, triglyceride, HOMA-IR, leptin and TNF-α as determinants of adiponectin revealed that BMI-z score was the only determinant for adiponectin (r:-0.45, p<0.0001). Adiponectin levels in hyperinsulinemic and impaired glucose tolerance groups (IGT) tended to be lower than in normoinsulinemic obese children, however, the difference was not significant. There was a weak negative correlation between adiponectin levels and increasing severity of insulin resistance (r=-0.23, p=0.005) in the groups of obese subjects. Mean serum adiponectin level in subjects with MS was lower than in subjects without MS (p=0.008).

CONCLUSIONS

Evaluation of serum adiponectin levels might contribute to an early intervention in obese children with MS.

Assessment of thyroid function during the long course of Hashimoto's thyroiditis in children and adolescents

CONTEXT

The prognosis of Hashimoto's thyroiditis (HT) in children and adolescents is not well known and studies reporting long-term outcome of the disease are scarce.

OBJECTIVE

To assess the thyroid hormone status during long-term follow-up and to establish the prognosis of children and adolescents with HT.

PATIENTS

One hundred and twenty-nine patients with HT were re-evaluated for thyroid hormone status after a mean follow-up period of 50 months.

RESULTS

Seventy-seven per cent of the euthyroid patients were still euthyroid, while 21.1% of these patients became hypothyroid at the time of re-evaluation. However, 69.5% of hypothyroid patients remained hypothyroid (overt or subclinical) and 30.5% recovered.

CONCLUSION

HT is a dynamic process. Thyroid functions can show variation during follow-up. Therefore, thyroid function tests should be repeated periodically to detect progression to hypothyroidism in initially euthyroid patients as well as reversibility of hypothyroidism.

Rare sex chromosome aneuploidies: 49,XXXXY and 48,XXXY syndromes

49,XXXXY and 48,XXXY syndromes are rare gonosomal aneuploidies in which the affected individuals present with characteristic facial and skeletal malformations, intrauterine growth retardation, and psychomotor retardation. Psychological, endocrinologic and orthopedic disorders constitute the major problems in the clinical follow-up. Sex chromosome abnormalities should especially be kept in mind in the evaluation of patients with micropenis, mental retardation and accompanying behavioral disturbances. Management mandates a multidisciplinary approach with pediatric endocrinology, pediatric surgery, orthopedics, psychiatry, and clinical genetic evaluations.

Hashimoto's thyroiditis in children and adolescents: a retrospective study on clinical, epidemiological and laboratory properties of the disease

Hashimoto's thyroiditis (HT) is the most common cause of goiter and acquired hypothyroidism in children and adolescents in iodine replete areas. To find out the clinical, epidemiological and laboratory characteristics of the disease in childhood, we reviewed files of 162 children and adolescents with HT followed in the Department of Pediatric Endocrinology, Hacettepe University Faculty of Medicine.

RESULTS

Female patients constituted 86.4% (n = 140) of all patients with a female:male ratio of 6.4. Mean age at diagnosis was 11.4 +/- 2.97 years (age range 4.4-16.5 years). At the time of diagnosis 43.2% of the patients (n = 70) were euthyroid, 24.1% (n = 39) had subclinical hypothyroidism, 21% (n = 34) had overt hypothyroidism, and 8.6% (n = 14) had overt and 3.1% (n = 5) subclinical hyperthyroidism.

CONCLUSIONS

Autoimmune thyroiditis is more frequent in females, and increases in frequency over age during childhood and adolescence. At the time of diagnosis, frequency of overt and subclinical hypothyroidism is similar to that of euthyroid goiter.

Thyroid involvement in Langerhans cell histiocytosis: a report of two cases and review of the literature

Langerhans cell histiocytosis (LCH) is a disorder with unclear etiology and pathogenesis characterized by abnormal clonal proliferation and accumulation of antigen presenting Langerhans' cells at various tissues and organs. Almost all organs or systems may be involved, and the prognosis depends on the involved sites and the presence of organ dysfunction. Thyroid tissue is a rarely affected site in children, and without histopathological evaluation it may be difficult to distinguish from other thyroid disorders because of the similar physical examination, laboratory and imaging findings. Here we report on two patients with histopathologically proven thyroid involvement of LCH. Additionally, the differential diagnosis of diffusely enlarged or multinodular thyroid glands in children is discussed, and a review of the literature of thyroid involvement in LCH is given. In the differential diagnosis of enlarged thyroid glands, especially in the presence of other endocrinological manifestations, LCH must be taken into consideration.

Inappropriate use of potent topical glucocorticoids in infants

Topical therapy with glucocorticoids (GCs) is used commonly in chronic dermatoses. Side effects are less common compared to systemic use; however, newer potent preparations may have serious side effects. A potential danger is their inappropriate use. Three infants who developed iatrogenic Cushing's syndrome and prolonged adrenal suppression in the course of GC therapy for simple diaper dermatitis are described. One patient also developed steatohepatitis which is uncommon with local GCs.

Cholestatic hepatitis as a result of severe cortisol deficiency in early infancy: report of two cases and review of literature

Cholestatic hepatitis is identified as one of the features of hypopituitarism in the newborn, but the exact etiology of cholestasis in these cases has not been well established yet. We report here two infants, one with isolated glucocorticoid deficiency and the other with multiple pituitary hormone deficiency, indicating primary and central adrenal insufficiency, respectively, who presented with recurrent hypoglycemic seizures and cholestatic hepatitis. Severe cortisol deficiency in these cases was suggested to be the cause of cholestatic hepatitis. Review of the literature and our cases showed that the cortisol deficiency in both primary and central adrenal insufficiency occurring only during neonatal and early infancy period cause cholestatic hepatitis. The severity and the age of onset of cortisol deficiency are suggested to be the important predictors of cholestatic hepatitis in childhood.

Marker assisted genetic analysis of non-brittle rachis trait in barley

Brittle rachis is a head shattering mechanism of barley. Two tightly linked complementary genes, btr1 and btr2, were believed to control the non-brittle rachis trait. Position of non-brittle rachis loci btr1btr2 on the short arm of Chromosome 3 was investigated using RFLP markers. Two approaches were employed. First, a Hordeum vulgare subsp. spontaneum fragment that confers brittleness in a cv. Bowman near isogenic line was detected. This fragment is 18-33 cM in length and contains MWG798B, ABG057, MWG014, BCD706 and KFP216 markers of the short arm of Chromosome 3. In the second approach, position of btr1 locus in a H. vulgare subsp. spontaneum (Wadi Qilt 23-38)xH. vulgare subsp. vulgare (cv. Harrington) cross was detected using a selective genotyping approach in BC2F1 generation. F-tests and analysis of genotypic compositions of BC2F1 lines showed that btr1 locus, and supposedly the tightly linked btr2 locus, is in 4.3 cM KFP216-RisP114 interval of short arm of Chromosome 3. Results also yielded clues for the presence of at least two additional loci that affect the non-brittle rachis trait. Allelism tests using genotypes with known non-brittle rachis gene compositions provided additional evidence for presence of such loci.

Ten-year experience in management of diabetic ketoacidosis and ketosis: 140 episodes at pediatric age

One hundred and forty episodes in 112 patients (58 boys) with diabetic ketoacidosis (96 episodes) and diabetic ketosis (44 episodes) were studied to elucidate the clinical and laboratory risk factors for altered level of consciousness at presentation and to analyze the outcome of a distinct protocol in the treatment of diabetic ketoacidosis. The patients were analyzed according to demographic data and clinical and laboratory findings at admission. The treatment protocol involved use of 0.45% sodium chloride (NaCl) in 2.5% dextrose as the initial fluid therapy following volume expansion. Dextrose content of the fluid was doubled once the serum glucose level fell below 250 mg/dl. The mean ages at presentation with diabetic ketoacidosis and ketosis were 10.3 +/- 4.4 and 10.2 +/- 4.0 years, respectively. Thirty-one percent of patients had altered consciousness at presentation. The level of consciousness correlated negatively with serum bicarbonate level (r=-0.485; p<0.001). A serum bicarbonate level below 15 mmol/L was a risk factor for altered consciousness. There was no correlation between effective osmolality and the level of consciousness. Serum effective osmolality above 320 mOsm/kg H2O did not appear to be a risk factor for altered consciousness. No mortality or any signs of clinical brain edema were observed in patients treated with the distinct treatment protocol. In conclusion, acidosis appears to be the major factor in the pathogenesis of altered consciousness at presentation. Serum effective osmolality does not seem to be a risk factor as suggested previously. Dextrose added to the infusion fluid early in treatment seems to prevent the development of brain edema, and this may be due to a protective effect of higher osmolality in the resultant solution.

A phenocopy of CAII deficiency: a novel genetic explanation for inherited infantile osteopetrosis with distal renal tubular acidosis

The rare bone thickening disease osteopetrosis occurs in various forms, one of which is accompanied by renal tubular acidosis (RTA), and is known as Guibaud-Vainsel syndrome or marble brain disease. Clinical manifestations of this autosomal recessive syndrome comprise increased bone density, growth failure, intracerebral calcification, facial dysmorphism, mental retardation, and conductive hearing impairment. The most common cause is carbonic anhydrase II (CAII) deficiency. Several different loss of function mutations in CA2, the gene encoding CAII, have been described. To date, there have been no exceptions to the finding of CAII deficiency in patients with coexistent osteopetrosis and RTA. Most often, the RTA is of mixed proximal and distal type, but kindreds are reported in which either distal or proximal RTA predominates. We report the molecular genetic investigation of two consanguineous kindreds where osteopetrosis and distal RTA (dRTA) were both manifest. One kindred harbours a novel homozygous frameshift alteration in CA2. In the other, CAII levels were normal despite a similar clinical picture, and we excluded defects in CA2. In this kindred, two separate recessive disorders are penetrant, each affecting a different, tissue specific subunit of the vacuolar proton pump (H(+)-ATPase), providing a highly unusual, novel genetic explanation for the coexistence of osteopetrosis and dRTA. The osteopetrosis is the result of a homozygous deletion in TCIRG1, which encodes an osteoclast specific isoform of subunit a of the H(+)-ATPase, while the dRTA is associated with a homozygous mutation in ATP6V1B1, encoding the kidney specific B1 subunit of H(+)-ATPase. This kindred is exceptional firstly because the coinheritance of two rare recessive disorders has created a phenocopy of CAII deficiency, and secondly because these disorders affect two different subunits of the H(+)-ATPase that have opposite effects on bone density, but which have only recently been determined to possess tissue specific isoforms.

Comparison of stimulated growth hormone levels in primed versus unprimed provocative tests. Effect of various testosterone doses on growth hormone levels

OBJECTIVE

To show the importance of priming prior to growth hormone (GH) stimulation tests in the diagnosis of GH deficiency, the effect of different doses and schedules of testosterone (T) on GH levels.

PATIENTS AND METHODS

Eighty-four prepubertal and early pubertal boys whose heights were 2 SD below the mean and height velocities <4 cm per year and who failed in GH stimulation tests were included in the study. The boys were divided into two groups: the first group consisting of 41 boys was primed with 62.5 mg/m(2) (low dose testosterone - LDT) and the second group consisting of 43 boys with 125 mg/m(2) depot testosterone (conventional dose testosterone - CDT) intramuscularly 1 week before the stimulation test. Twenty-one boys out of 36 who failed in GH stimulation tests after one dose T injection were treated with three doses of 62.5 mg/m(2) T (multiple dose testosterone - MDT) injections monthly and retested.

RESULTS

The GH levels increased from 4.80 +/- 2.78 to 11.50 +/- 8.84 ng/ml and from 4.76 +/- 2.46 to 12.98 +/- 8.30 ng/ml by priming with LDT and CDT respectively. The increment of mean GH levels by both LDT and CDT were found to be similar (p = 0.443). The peak GH levels were found to be elevated >10 ng/ml in 22/41 (54%) and 26/43 (60%) who received LDT and CDT respectively (p = 0.528). The mean GH level of 21 boys who received MDT was increased from 5.38 +/- 2.50 ng/ml (by priming with one dose T) to 10.19 +/- 6.13 ng/ml (p = 0.004). Twelve (57%) of 21 boys who received MDT responded to GH stimulation test >10 ng/ml. The T level increased from 0.71 +/- 0.97 to 4.54 +/- 2.80 ng/ml by LDT (p < 0.001) and from 0.65 +/- 0.71 to 7.18 +/- 3.18 ng/ml by CDT (p < 0.001). The increment of T level was higher by CDT than LDT (p = 0.001). There was no correlation between T and peak GH levels after priming.

CONCLUSION

LDT is as effective as CDT in priming of GH stimulation tests. The ones who failed in GH stimulation tests after one dose T injection can be primed with MDT. The stimulated GH level after priming was related neither to the plasma level of T nor the dose of T.