A personal series of 100 children operated for Cushing's disease (CD): optimizing minimally invasive diagnosis and transnasal surgery to achieve nearly 100% remission including reoperations

Background Transnasal surgery (TNS) is the first choice in the treatment of pediatric Cushing's disease. The question is how can high remission rates be achieved with minimally invasive investigations and TNS whilst avoiding radiotherapy or bilateral adrenalectomy in children. Methods Data from a published series 1 (n=55) of surgeon DKL will be compared with his recent series 2 (n=45) until 2009. All patients were operated by direct transnasal microsurgery. Over time, inferior petrosal sinus sampling (IPSS) was replaced by cavernous sinus sampling (CSS), restricted to unclear cases without increase of salivary cortisol in corticotropin-releasing hormone-test, difficult sellar anatomy or negative magnetic resonance imaging (MRI). Multiple direct intra-operative micro-cytology, micro-doppler and adequate visualization techniques are described. Results In series 1, IPSS was performed in 13 (24%) of whom 46% had false adenoma lateralization. All adenomas could be removed with extensive pituitary exploration. Three patients had early successful re-surgery. In series 2, with more refined MRI and endocrinology, CSS was used in only seven patients (15%) and all micro-adenomas were correctly localized. In three of four patients with persistent cortisol excess, repeat-TNS was necessary and successful. Side effects of TNS were minimal. Recurrence rates were 16% and 11% in series 1 and 2, respectively. Only four of 100 children with invasive adenomas were irradiated, significantly less than in other experienced pediatric centers. Conclusions Thus, 98% remission rate could be achieved with fewer invasive pre-surgical investigations, such as central catheter studies, refined TNS and early repeat-TNS. Repeat-TNS in recurrences minimized the need for irradiation.

Recurrences of Pituitary Adenomas or Second De Novo Tumors: Comparisons with First Tumors

BACKGROUND

Recurrences of pituitary adenomas are not so rare.

METHODS

In the German Registry of Pituitary Tumors, more than 12,000 surgical specimens were collected between 1967 and 2012, of which 312 patients with altogether 334 recurrences (n = 646 specimens) were included in our study.

RESULTS

The histopathology of 162 recurrent adenomas could be compared with the original tumor and 37 second recurrences could be compared with the first recurrence. Comparing the proliferation index (Ki-67) of the original and the first recurrent tumor (n = 162), we found an unchanged index in 43 cases (26%), whereas in 69 cases (43%) the index increased and in 50 cases (31%) it decreased. Comparing the first with the second recurrence (n = 37), we found an unchanged index in 8 cases (22%), an increased index in 15 cases (40%), and a decreased index in 14 cases (38%). The third recurrence showed an unchanged index in 1 case (20%), an increased index in 2 cases (40%), and a decreased index in 2 cases (40%). p53 was unchanged in recurrences in 44% of cases, increased in 33%, and decreased in 22%. In 4 cases, adenomas developed into adenomas with strongly increased proliferation (formerly atypical adenomas, now aggressive adenomas) for the first recurrence, and 9 recurrences became aggressive adenomas. A change of tumor type without change of the common transcription factor occurred in 82 cases.

CONCLUSIONS

A second independent de novo adenoma was present in 10 cases, probably due to changes of transcription factors.

Low dose growth hormone treatment in infants and toddlers with Prader-Willi syndrome is comparable to higher dosage regimens

OBJECTIVE

Evaluate benefit and risk of low dose growth hormone treatment (GHT, 4.5mg/m²/week) in very young children with Prader-Willi Syndrome (PWS).

DESIGN

Prospective longitudinal clinical intervention.

METHODS

We evaluated 31 infants (aged 2-12months) and 42 toddlers (13-24months) from the PWS-OZGROW database for height, weight and BMI using the World Health Organization standard deviation scores (SDS_WHO) and PWS specific BMI (SDS_PWS), bone age, insulin-like growth factor 1 (IGF-I) levels and adverse events over 3years of GHT.

RESULTS

At commencement of GHT infants had a lower BMI SDS_WHO (-0.88 vs 0.40) than toddlers, while toddlers had a lower height SDS_WHO (-1.44 vs -2.09) (both P<0.05). All increased height SDS_WHO (2year delta height infants +1.26 SDS, toddlers+1.21 SDS), but infants normalised height sooner, achieving a height SDS of -0.56 within 1year, while toddlers achieved a height SDS of -0.88 in two years. BMI SDS_WHO increased, while BMI SDS_PWS decreased (both P<0.0001) and remained negative. The GHT response did not differ with gestation (preterm 23%) or genetic subtype (deletion vs maternal uniparental disomy). Bone age advancement paralleled chronological age. All children had low serum IGF-I at baseline which increased, but remained within the age-based reference range during GHT (for 81% in first year). Four children had spinal curvature at baseline; two improved, two progressed to a brace and two developed an abnormal curve over the observation period. Mild to severe central and/or obstructive sleep apnoea were observed in 40% of children prior to GHT initiation; 11% commenced GHT on positive airway pressure (PAP), oxygen or both. Eight children ceased GHT due to onset or worsening of sleep apnoea: 2 infants in the first few months and 6 children after 6-24months. Seven resumed GHT usually after adjusting PAP but five had adenotonsillectomy. One child ceased GHT temporarily due to respiratory illness. No other adverse events were reported. Two children substantially improved their breathing shortly after GHT initiation.

CONCLUSION

Initiation of GHT in infants with 4.5mg/m²/week was beneficial and comparable in terms of auxological response to a dose of 7mg/m²/week. Regular monitoring pre and post GH initiation assisted in early detection of adverse events. IGF-I levels increased with the lower dose but not excessively, which may lower potential long-term risks.

Identification of endothelin-converting enzyme-2 as an autoantigen in autoimmune polyendocrine syndrome type 1

Autoimmune polyendocrine syndrome type 1 (APS1) is a rare monogenic autoimmune disorder caused by mutations in the autoimmune regulator (AIRE) gene. High titer autoantibodies are a characteristic feature of APS1 and are often associated with particular disease manifestations. Pituitary deficits are reported in up to 7% of all APS1 patients, with immunoreactivity to pituitary tissue frequently reported. We aimed to isolate and identify specific pituitary autoantigens in patients with APS1. Immunoscreening of a pituitary cDNA expression library identified endothelin-converting enzyme (ECE)-2 as a potential candidate autoantigen. Immunoreactivity against ECE-2 was detected in 46% APS1 patient sera, with no immunoreactivity detectable in patients with other autoimmune disorders or healthy controls. Quantitative-PCR showed ECE-2 mRNA to be most abundantly expressed in the pancreas with high levels also in the pituitary and brain. In the pancreas ECE-2 was co-expressed with insulin or somatostatin, but not glucagon and was widely expressed in GH producing cells in the guinea pig pituitary. The correlation between immunoreactivity against ECE-2 and the major recognized clinical phenotypes of APS1 including hypopituitarism was not apparent. Our results identify ECE-2 as a specific autoantigen in APS1 with a restricted neuroendocrine distribution.

Population-based incidence of diabetes in Australian youth aged 10-18 yr: increase in type 1 diabetes but not type 2 diabetes

BACKGROUND

Global incidence of childhood type 2 diabetes has increased, with a greater rise amongst certain ethnic groups.

OBJECTIVES

To examine the change in the incidence of type 1 and type 2 diabetes in Australian youth, aged 10-18 yr, in New South Wales, Australia.

METHODS

Prospective population-based incidence study (2001-2008). Primary case ascertainment was from the Australasian Paediatric Endocrine Group Diabetes Register, secondary independent ascertainment from the National Diabetes Register.

RESULTS

There were 202 incident cases of type 2 diabetes (96 boys, 48%). The mean age at diagnosis (±SD) was 14.6 ± 2.5 yr; 93% were overweight (International Obesity Taskforce Grade ≥1). Mean HbA1c was 8.8 ± 2.8%. Ethnicity was Caucasian 31%, Indigenous Australian 20%, Southeast Asian 11%, North African/Middle Eastern 9%, and NewZealander/Melanesian/Polynesian 8%. The mean annual incidence of type 2 diabetes was 3.0 per 100 000 per year (95% confidence interval (CI): 2.6-3.4) and did not change over time. The mean annual incidence of type 1 diabetes was 22.0 per 100 000 per year (95% CI: 20.8-23.1), and increased by 3.8% per year [incidence rate ratio IRR: 1.04, 95% CI: 1.02-1.06, p = 0.001]. Incidence was higher in Indigenous vs. non-Indigenous youth, IRR: 6.9 (95% CI: 4.7-10.2, p < 0.001).

CONCLUSION

In 10-18 yr old youth, in Australia, the incidence of type 2 diabetes has remained steady during the last decade; however, the incidence of type 1 diabetes continues to rise. Most common diabetes in Australian youth is type 1 diabetes.

A rare case of pituitary infarction leading to spontaneous tumour resolution and CSF-sella syndrome in an 11-year-old girl and a review of the paediatric literature

Pituitary infarction or apoplexy with spontaneous cure of the underlying pituitary adenoma is rare. In the paediatric population, we found only a few reported cases. We report a rare case of pituitary infarction progressing to CSF-sella syndrome (or empty sella) in an 11-year-old girl. She presented with sudden onset vomiting, moderate headaches, lethargy, weight loss, and tall stature above her mid-parental height. She did not have any severe symptoms of apoplexy. Her clinical and radiological findings suggested infarction of a pituitary lesion, such as a pituitary adenoma or infarction of a cystic lesion, such as a Rathke's cleft cyst. In this report, we discuss her case of probable infarction of a growth hormone secreting adenoma with a phase of accelerated growth ending up with total anterior pituitary insufficiency. The differential diagnosis and review of the rare cases of paediatric pituitary infarction in the literature will be discussed.

Intermediate lobe immunoreactivity in a patient with suspected lymphocytic hypophysitis

Lymphocytic hypophysitis is an organ-specific autoimmune disease characterised by destruction of pituitary hormone-secreting cells due to attack by self-reactive T lymphocytes. The spectrum of pituitary autoantibodies characterised by indirect immunofluorescence (IF) in these patients has not been substantially defined. The purpose of this study was to determine the spectrum of pituitary autoantibodies in 16 lymphocytic hypophysitis patients. Pituitary sections were prepared from guinea pigs and sera from 16 lymphocytic hypophysitis patients (13 biopsy proven and 3 suspected cases) and 13 healthy controls were evaluated for immunoreactivity to the pituitary tissue by immunofluorescence. A single patient was found to have high titre pituitary autoantibodies against guinea pig pituitary tissue. Immunoreactivity was directed against cells of the intermediate lobe. We present the case report of the patient who is a 24 year old woman that presented with headaches, polyuria and polydipsia. A uniformly enlarged pituitary mass was visible on MRI and a diagnosis of suspected lymphocytic hypophysitis was made. Based on our IF study, we postulate this patient has an autoimmune process directed towards the major cell type in the intermediate lobe, the melanotroph. Pre-adsorption with peptides representing adrenocorticotropic hormone, α-melanocyte stimulating hormone or β-endorphin did not affect the IF signal suggesting our patient's pituitary autoantibodies may target some other product of Proopiomelanocortin (POMC) processing, such as corticotrophin-like intermediate peptide or γ-lipoprotein. Alternatively, the autoantibodies may target a peptide completely unrelated to POMC processing.

Non-invasive detection of microvascular changes in a paediatric and adolescent population with type 1 diabetes: a pilot cross-sectional study

BACKGROUND

The detection of microvascular damage in type 1 diabetes is difficult and traditional investigations do not detect changes until they are well established. The purpose of this study was to investigate the combined ability of nailfold capillaroscopy, laser Doppler flowmetry, retinal vessel analysis and 24-hr ambulatory blood pressure monitoring to detect early microvascular changes in a paediatric and adolescent population with type 1 diabetes.

METHODS

Patients aged between 8 - 18 years with type I diabetes and no other autoimmune conditions were studied. The participants underwent the above cardiac and vascular investigations in a single three-hour session. Standard parameters including HbA1c were also investigated. Associations between all parameters were described by correlation analysis. Fisher's exact and t-tests determined the association with clinical findings.

RESULTS

26 participants were recruited. The mean HbA1c was 8.1% (SD ± 1.1) with a mean duration of type 1 diabetes of 7.9 years (SD ± 3.4). Three participants had microalbuminuria and one had early signs of retinopathy. Participants with microvascular complications had more avascular areas on nailfold capillaroscopy (p = 0.03). Recent HbA1c was positively associated with the number of nailfold microhaemorrhages (p = 0.03) Decreased baseline perfusion by laser Doppler flowmetry was associated with increased capillary density (p = 0.001) and an increased number of microaneurysms (p = 0.04) on nailfold capillaroscopy.

CONCLUSIONS

This pilot study has shown that in children and adolescents with established type 1 diabetes, abnormal microvasculature can be detected by these investigations. These markers were also positively associated with evidence of suboptimal diabetes control as assessed by HbA1c. Further research will be necessary to determine the practical role of these investigations in the management and progress of the complications of type 1 diabetes.

TRIAL REGISTRATION

Clinical Trial number NCT01279928, ClinicalTrials.gov.

Novel use of endogenous GH-measurement directly after transsphenoidal microsurgery in acromegaly treated with pegvisomant

OBJECTIVE

The GH receptor antagonist pegvisomant is increasingly used as therapy in acromegaly. Pituitary surgery might be indicated on pegvisomant treatment, due to side effects, adenoma growth or intention to cure after primary treatment. This study was initiated to clarify if, and when, GH measurement could be useful postoperatively with an assay specific for endogenous GH that does not cross-react with pegvisomant.

METHODS

This study was designed as a prospective study in 2006 with the German Pituitary Working Group. Only 2 cases with potentially resectable adenomas from the German Pegvisomant Observational Study (GPOS) had been operated. Now with a post-operative follow-up of more than 5 years in these 2 cases, the usefulness of immediate pre-operative GH measurement shortly after pegvisomant treatment was evaluated.

RESULTS

In both patients a steep decline of endogenous GH after transnasal microsurgery could be proven by using the special GH assay after near radical or radical removal, of the GH secreting adenomas respectively. Conventional GH assays showed no effect. GH half-life was more than 20 min in the patient with a small invasive residual adenoma and less than 20 min in the cured patient. Endogenous GH-levels declined to less than 1 ng/ml in the days after surgery in the patient with long-term cure.

CONCLUSION

Measurement of endogenous GH in this special subgroup of patients under pegvisomant therapy can be used to decide upon early reoperation. Thus the beneficial effect of pegvisomant on acromegalic symptoms can be kept without interfering with post-operative monitoring of GH levels.

Identification of TPIT and other novel autoantigens in lymphocytic hypophysitis: immunoscreening of a pituitary cDNA library and development of immunoprecipitation assays

BACKGROUND

Lymphocytic hypophysitis is an organ-specific autoimmune disease of the pituitary gland. A specific and sensitive serological test currently does not exist to aid in the diagnosis.

OBJECTIVE

To identify target autoantigens in lymphocytic hypophysitis and develop a diagnostic assay for these proteins.

DESIGN/METHODS

A pituitary cDNA expression library was immunoscreened using sera from four patients with lymphocytic hypophysitis. Relevant cDNA clones from screening, along with previously identified autoantigens pituitary gland-specific factor 1a and 2 (PGSF1a and PGSF2) and neuron-specific enolase (NSE) were tested in an in vitro transcription and translation immunoprecipitation assay. The corticotroph-specific transcription factor, TPIT, was investigated separately as a candidate autoantigen.

RESULTS

Significantly positive autoantibody reactivity against TPIT was found in 9/86 hypophysitis patients vs 1/90 controls (P = 0.018). The reactivity against TPIT was not specific for lymphocytic hypophysitis with autoantibodies detectable in the sera from patients with other autoimmune endocrine diseases. Autoantibodies were also detected against chromodomain-helicase-DNA binding protein 8, presynaptic cytomatrix protein (piccolo), Ca(2+)-dependent secretion activator, PGSF2 and NSE in serum samples from patients with lymphocytic hypophysitis, but at a frequency that did not differ from healthy controls. Importantly, 8/86 patients with lymphocytic hypophysitis had autoantibodies against any two autoantigens in comparison with 0/90 controls (P = 0.0093).

CONCLUSIONS

TPIT, a corticotroph-specific transcription factor, was identified as a target autoantigen in 10.5% of patients with lymphocytic hypophysitis. Further autoantigens related to vesicle processing were also identified as potential autoantigens with different immunoreactivity patterns in patients and controls.

Increased detection of cystic-fibrosis-related diabetes in Australia

OBJECTIVES

To estimate the incidence of cystic-fibrosis-related diabetes (CFRD) in youth from New South Wales (NSW) and the Australian Capital Territory (ACT), Australia and to examine demographic/clinical features at diagnosis.

METHODS

Incident cases of CFRD in young people aged ≤ 18 years diagnosed during 2000 to 2008 were identified from four paediatric cystic fibrosis (CF) clinics and the NSW/ACT Australasian Paediatric Endocrine Group Diabetes Register.

RESULTS

CFRD was diagnosed in 41 cases (59% girls). The estimated mean annual incidence of CFRD among patients with CF was 9.4 per 1000 person years (95% CI 6.8 to 12.8). Incidence increased from 2.0 per 1000 person years in 2000 to 22.1 per 1000 in 2008 (incidence RR 1.3, 95% CI 1.1 to 1.4). Haemoglobin A1c (HbA1c) was abnormal in the majority at diagnosis: median HbA1c was 6.9% (6.2-8.1%). More cases were diagnosed using an oral glucose tolerance test in 2007-2008 compared with previous years (61% vs 6%, p<0.001).

CONCLUSIONS

CFRD is increasingly recognised and now affects approximately one in five young people with CF. The rising incidence is likely to be due to increased detection, resulting from greater awareness and changes in screening practices. Widespread uptake of consensus guidelines for screening will ensure accurate case detection, but will also impact on patient care and resource allocation.

Changes in altitude cause unintended insulin delivery from insulin pumps: mechanisms and implications

OBJECTIVE

Children and adults with type 1 diabetes who receive insulin pump therapy have reported hypoglycemia during air travel. We studied the effects of atmospheric pressure on insulin pump delivery.

RESEARCH DESIGN AND METHODS

Ten insulin pumps were connected to capillary tubes. The effects of changes in ambient pressure on insulin delivery, bubble formation, bubble size, and cartridge plunger movement were analyzed.

RESULTS

During a flight (200 mmHg pressure decrease), excess insulin delivery of 0.623% of the cartridge volume occurred (P < 0.001, Student t test). In hypobaric chamber studies, bubbles developed in the insulin when the pressure decreased and displaced the insulin out of the cartridge. Pre-existing bubbles changed in size consistent with Boyle law. Cartridge plunger movement did not occur in normal flight conditions but did occur when catastrophic plane depressurization was mimicked.

CONCLUSIONS

Atmospheric pressure reduction causes predictable, unintended insulin delivery in pumps by bubble formation and expansion of existing bubbles.

Normal cortisol response on low-dose synacthen (1 microg) test in children with Prader Willi syndrome

INTRODUCTION

It has been postulated that central adrenal insufficiency (CAI), resulting from hypothalamic dysfunction, may contribute to the increased unexplained death rates in Prader Willi syndrome (PWS). A study using the overnight metyrapone test reported a 60% prevalence of CAI in children with PWS. We used a low-dose Synacthen test to screen for CAI in children with PWS.

METHODS

We studied 41 children with genetic diagnosis of PWS [20 males; mean age, 7.68 (±5.23) yr] in five pediatric endocrinology centers in Australasia. All participants were randomly selected, and none had a history of Addisonian crisis. Ten of the cohort were receiving sex hormone therapy, 19 were receiving GH, and four were receiving T4. Their mean body mass index z-score was +1.48 (±1.68). Baseline morning ACTH and cortisol levels were measured, followed by iv administration of 1 μg Synacthen. Post-Synacthen cortisol levels were measured at 30 min, and a cortisol level above 500 nmol/liter was considered normal.

RESULTS

The mean baseline ACTH and cortisol were 15 (±14) ng/liter and 223 (±116) nmol/liter, respectively. The mean 30-min plasma cortisol was 690 (±114) nmol/liter, and the average increase from baseline was 201%.

CONCLUSIONS

Our result suggests that CAI is rare in children with PWS.

The A, B, C, D of hypercalcaemia in Down syndrome

Hypercalcaemia in infants with Down syndrome is an uncommon condition with only five previous case reports. The patients often present in the toddler years with the classical triad of Down syndrome, biochemical hypercalcaemia, and nephrocalcinosis. We present the sixth case and second male with this condition and further review the clinical details of this under-recognised condition and stratify the diagnostic criteria. The management mandates a reduction in calcium intake as a first step. The natural history of the various aspects of this condition is also considered.

Pituitary autoantibodies in autoimmune polyendocrine syndrome type 1

Autoimmune polyendocrine syndrome type 1 (APS1) is a rare autosomal recessive disorder caused by mutations in the autoimmune regulator (AIRE) gene. High titer autoantibodies (Aabs) toward intracellular enzymes are a hallmark for APS1 and serve as diagnostic markers and predictors for disease manifestations. In this study, we aimed to identify pituitary autoantigens in patients with APS1. A pituitary cDNA expression library was screened with APS1 sera and a tudor domain containing protein 6 (TDRD6) cDNA clone was isolated. Positive immunoreactivity against in vitro translated TDRD6 fragments was shown in 42/86 (49%) APS1 patients but not in patients with other autoimmune diseases or in healthy controls. By using immunohistochemistry, sera from 3/6 APS1 patients with growth hormone (GH) deficiency showed immunostaining of a small number of guinea pig anterior pituitary cells, and 40-50% of these cells were GH-positive. No such immunostaining was seen with sera from healthy controls. The APS1 Aab-positive, GH-negative cells may represent a novel subpopulation of anterior pituitary cells. In addition, 4/6 patient sera showed staining of a fiber-plexus in the pituitary intermediate lobe recognizing enzymes of monoamine and GABA synthesis. Thus, we have identified TDRD6 as a major autoantigen in APS1 patients and shown that several sera from GH-deficient patients stain specific cell populations and nerves in the pituitary gland.

Pituitary autoantibodies in autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED)

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is an autosomal recessive disease due to mutations in the AIRE (AutoImmune REgulator) gene. The role of pituitary autoimmunity in APECED is not known. We determined the prevalence of pituitary autoantibodies in a cohort of 67 Finnish patients with APECED from 217 serum samples collected over 26 years by one investigator. Overall, autoantibodies to the 49 kDa cytosolic autoantigen, human pituitary enolase were detected in 39 of the 67 patients (58%). On their first sample, 25 patients had autoantibodies compared to 5 of 68 controls (chi-square, 1df=17.11, p< 0.001; OR=7.32), but subsequently 14 patients seroconverted between 10 and 53 years of age. Once seropositive, all but two of the patients maintained their positive autoantibody status, even over many years. In the current study all but 7 of the 19 patients known to have high titre anti-candidal enolase antibodies had developed autoantibodies directed against human pituitary enolase. Other pituitary autoantibody reactivities were detected against cytosolic proteins of molecular weights 40-, 45-, 60- and 105 kDa in 15%, 16%, 12% and 3% of patients respectively. Autoantibodies to pituitary enolase are markers of neuroendocrine autoimmunity but seem not to be associated with clinical hypopituitarism in APECED patients.

Prevalence of diabetes complications 6 years after diagnosis in an incident cohort of childhood diabetes

AIMS

To examine the prevalence of early diabetes complications 6 years after diagnosis of diabetes. The hypothesis that initial contact with a multidisciplinary team would be associated with a reduced risk of microvascular complications was tested in this cohort.

METHODS

Participants were recruited from an incident cohort of children aged < 15 years diagnosed between 1990 and 1992 in NSW, Australia. Initial management at a teaching hospital was documented at case notification. At 6 years, health care questionnaires and complications were assessed: retinopathy by 7-field stereoscopic retinal photography and elevated albumin excretion rate (AER) defined as the median of three overnight urine collections > or = 7.5 microg/min. Case attainment was 58% (209/361) with participants younger than non-participants and more likely living in an urban than rural location.

RESULTS

Retinopathy was present in 24%, median AER > or = 7.5 microg/min in 18%, and median AER > or = 20 microg/min in 2%. In multivariate analysis, initial management at a teaching hospital or consultation with all three allied health professionals combined with pubertal staging and cholesterol or HbA1c were all determinants of risk for retinopathy.

CONCLUSIONS

Early retinopathy and elevated AER are common in children 6 years after diagnosis. Initial allied health contact and management at a teaching hospital were associated with a reduced risk of microvascular complications in this cohort.

Autoantibodies against pituitary proteins in patients with adrenocorticotropin-deficiency

BACKGROUND

An autoimmune cause of adrenocorticotropin (ACTH)-deficiency is presented, as it is known to be a characteristic feature of lymphocytic hypophysitis, a disease of the pituitary gland considered to be autoimmune.

MATERIALS AND METHODS

The aim of this study was twofold: (1) to evaluate the occurrence of pituitary autoantibodies and (2) to correlate it to clinical and immunological features in a large group of patients with ACTH-deficiency of possible autoimmune aetiology. Sixty-five patients with ACTH-deficiency and 57 healthy subjects participated in the study. Pituitary autoantibodies were measured by an immunoblotting assay with human pituitary cytosol as antigen.

RESULTS

Autoantibodies to a novel 36-kDa pituitary autoantigen were seen in sera from 18.5% (12/65) patients and only 3.5% (2/57) of control subjects (P = 0.0214). When taking only those subjects with strong immunoreactivity into account, the significance was lost; P = 0.3642. Immunoreactivity to a 49-kDa pituitary autoantigen was observed in 21.5% (14/65) of ACTH-deficient patients compared with 8.8% (5/57) of control subjects (P = 0.0910). This 49-kDa pituitary autoantigen has recently been identified as neurone-specific enolase and a candidate marker for neuroendocrine autoimmunity. Clinical parameters in patients with positive versus those with negative pituitary immunoreactivity did not differ. However, autoantibodies to thyroglobulin were positively correlated to immunoreactivity against the 36-kDa pituitary autoantigen (P = 0.014).

CONCLUSIONS

Our findings of pituitary autoantibodies in patients' sera support the theory that an autoimmune destruction of corticotrophs may be the underlying cause of hormonal deficit in some patients with ACTH-deficiency.

Phenotype-genotype correlations in a series of wolfram syndrome families

OBJECTIVE

Wolfram syndrome is an extremely rare autosomal-recessive disorder that predisposes the development of type 1 diabetes in association with progressive optic atrophy. The genetic basis of this disease has been shown to be due to mutations in the WFS1 gene. The WFS1 gene encodes a novel transmembrane protein called wolframin, which recent evidence suggests may serve as a novel endoplasmic reticulum calcium channel in pancreatic beta-cells and neurons. Genotype-phenotype correlations in this syndrome are becoming apparent and may help in explaining some of the variable characteristics observed in this disease.

RESEARCH DESIGN AND METHODS

In this report, we have studied 13 patients with Wolfram syndrome from nine families to further define the relationship between mutation site and type with specific disease characteristics.

RESULTS

A severe phenotype was seen in patients with mutations in exon 4 and with a large deletion encompassing most of exon 8. In total, nine novel mutations were identified as well as three new silent polymorphisms.

CONCLUSIONS

Similar to all other mutation reports, most causative changes identified in the WFS1 gene occurred in exon 8, and only one was identified outside this region in exon 4.

Sudden death in growth hormone-treated children with Prader-Willi syndrome

A 4-year-old boy with Prader-Willi syndrome died suddenly while asleep on day 67 of growth hormone treatment. During treatment, snoring had worsened. Autopsy showed multifocal bronchopneumonia. This case and two others recently published suggest that growth hormone may be associated with obstructive apnea, respiratory infection, and sudden death in this condition.

A compound heterozygote case of type II aldosterone synthase deficiency

An infant with failure to thrive, persistent hyponatremia and episodic vomiting and diarrhea was admitted to hospital at 9 months of age, and the diagnosis of type II aldosterone synthase deficiency was confirmed by plasma and urinary steroid determinations. The entire coding sequence of the aldosterone synthase gene (CYP11B2) was determined (both strands) in the affected infant, an unaffected sibling, and both parents. An exon 3 mutation (C554T, leading to amino acid T185I) was found in the father and both siblings, and an exon 9 mutation (A1492G, leading to T498A) was found in the affected infant and the mother. Expression of the mutant sequences in COS cells showed steroidogenic patterns typical of aldosterone synthase type II deficiency, including very low levels of aldosterone synthesis (< or =0.5% of wild-type enzyme) consistent with the low aldosterone levels in the patient's plasma. Both mutations in this compound heterozygote localize to the beta 3-sheet in the cytochrome P450 enzyme structure, as does the previously characterized R181W mutation. This region of the enzyme is not part of the putative structural core, but mutations to this region suggest that it is important for conferring the unique ability of aldosterone synthase to catalyze efficient oxygenation of the C(18) carbon of steroid substrates.

Pituitary autoimmunity in patients with Sheehan's syndrome

Postpartum hemorrhage (PPH) is a frequent complication of pregnancy in India. Sheehan's description of postpartum hypopituitarism promoted the belief that PPH leads to necrosis of the enlarged pituitary gland of pregnancy and hypopituitarism. However, slow clinical progression suggests factors other than ischemia in its pathogenesis. Tissue necrosis could release sequestered antigens, triggering autoimmunity of the pituitary and delayed hypopituitarism in Sheehan's syndrome. Twenty-six consecutive patients with postpartum hypopituitarism were studied, 19 with Sheehan's syndrome based on a history of PPH and hormone profile suggesting pituitary failure [mean (SD) age 32.7 +/- 6.4 yr, duration of illness 5.5 +/- 3.1 yr], and seven patients with no history of PPH, categorized as "Other." Pituitary imaging and basal T(4), TSH, cortisol, LH, FSH, 17beta-estradiol, and autoantibodies against pituitary (PitAb) and thyroid (TMA) were evaluated. Controls included 28 healthy females without prior conception (22 +/- 5 yr) and 28 with prior conception (26 +/- 5 yr). Twelve of 19 (63.1%) patients with Sheehan's syndrome and one of seven in the Other group had PitAb against the 49-kDa autoantigen; neuron-specific enolase. Four of 28 (14.2%) controls without prior conception and 5 of 28 (17.8%) controls with prior conception had PitAb positivity (P < 0.001 and <0.01 vs. Sheehan's syndrome, respectively). There was no significant difference in the mean serum hormone values and TMA positivity between patients with Sheehan's syndrome and the Other group as well as patients with or without PitAb positivity. Pituitary autoimmunity may play a role in the cause of hypopituitarism following PPH.

Pituitary autoantibodies in lymphocytic hypophysitis target both gamma- and alpha-Enolase - a link with pregnancy?

The first target autoantigen to have been identified in lymphocytic hypophysitis is a 49 kDa protein, identified as alpha-enolase. Pituitary autoimmunity is strongly associated with pregnancy and we have shown that pituitary autoantibodies from patients with peripartum lymphocytic hypophysitis also recognise enolase in the placenta. Enolase exists in different forms as a number of isoenzymes, which are homo- or heterodimers of three subunits, alpha, beta and gamma. alphaalpha-enolase is ubiquitous, betabeta-enolase is muscle-specific and gammagamma-enolase, which is restricted to neuronal tissue and neuroendocrine cells, is known as neuron-specific enolase (NSE). NSE is expressed in normal human pituitary and pituitary neoplasms. The current study investigated which isoforms of enolase in pituitary and placenta reacted with the sera of patients with lymphocytic hypophysitis. Immunoblotting of two-dimensional gels of human pituitary cytosolic proteins showed that autoantibodies in patient sera react with both an acidic form, and more neutral forms of enolase. Immunoblotting with a monoclonal antibody to NSE confirmed the identity of the acidic enolase isoform as the gammagamma-isoform in both pituitary and placental samples. Gamma-enolase, i.e. NSE, was detected by immunohistochemistry in term placenta in decidua, syncytiotrophoblasts, anchoring villi and terminal villi. Our study is the first to describe the cellular localisation of NSE in normal human placenta, thus establishing a direct link between pituitary and placental autoantigens. This link provides a theoretical basis for the strong prediliction of lymphocytic hypophysitis to occur during or after pregnancy.

Identification of the 49-kDa autoantigen associated with lymphocytic hypophysitis as alpha-enolase

Lymphocytic hypophysitis is part of the spectrum of organ-specific autoimmune diseases, and although its histopathology is well documented, its pathogenesis is unclear. Serum autoantibodies directed against a 49-kDa cytosolic protein are detected by immunoblotting in 70% of patients with biopsy-proven lymphocytic hypophysitis. Here we report the purification and identification of this first target autoantigen in lymphocytic hypophysitis. The autoantigen has a molecular mass of 49 kDa, a cytosolic localization, and a ubiquitous tissue distribution. The 49-kDa protein was purified from monkey brain and human placental cytosol. Limited amino acid sequencing after proteolytic digestion of the human placental protein showed identity with alpha-enolase. The identification was confirmed using sera from patients with pituitary autoimmunity, which strongly reacted with recombinant human alpha-enolase and yeast enolase, but not with rabbit muscle beta- enolase. This indicates that the immunoreactive epitopes are largely conserved from yeast to human, but are not present in beta-enolase. alpha-Enolase autoantibodies are not specific to pituitary autoimmune disease and have been reported in other autoimmune diseases. However, this study is the first to indicate a role for alpha-enolase as an autoantigen in lymphocytic hypophysitis.

Clinical and endocrine characteristics in atypical and classical growth hormone insensitivity syndrome

OBJECTIVE

Classical growth hormone insensitivity syndrome (GHIS) comprises a dysmorphic phenotype, extreme short stature (height SDS < 3), normal GH and low IGF-I and IGFBP-3. Wide clinical variation is recognised with classical and atypical forms. We aimed to delineate features of the milder "atypical" GHIS phenotype, and to determine whether this correlates with milder auxological and biochemical features.

METHODS

Fifty-nine patients from a European series of 82 patients with GHIS, with strict diagnostic criteria of GHIS, were studied and assigned to classical or atypical GHIS groups according to facial phenotype, i.e. "classical" required 2 of 3 recognized GHIS features (frontal bossing, mid-facial hypoplasia and depressed nasal bridge), "atypical" required 0 or 1 of these facial features. Classical and atypical GHIS groups were compared in terms of (1) phenotypic features, including high-pitched voice, sparse hair, blue sclera, hypoglycaemia, microphallus, (2) birth length, height SDS, and (3) basal IGF-I, IGF-II, IGFBP-1, IGFBP-3, GHBP and increase in IGF-I on IGF-I generation testing.

RESULTS

Fifty patients [24 males, 26 females, aged 8.6 +/- 4.6 years (mean +/- SD)] had "classical GHIS", 9 patients (7 males, 2 females, aged 7.8 +/- 4.1 years) had "atypical GHIS", 7 with normal facies. Atypical GHIS patients had lesser height deficit (Ht SDS -4.0 +/- 1.4) compared to classical GHIS (-6.7 +/- 1.4), less reduction in IGFBP-3 SDS (atypical -5.5 +/- 3.3; classical -8.6 +/- 2.4), and more had normal GHBP (>10% binding). Other variables were also less frequent in atypical GHIS patients: high-pitched voice 11% (70% classical), sparse hair 11% (42% classical), blue sclera 0% (38% classical), hypoglycaemia 11% (42% classical), and microphallus 14% (1 of 7 males), compared to 79% of classical (19 of 24 males).

CONCLUSIONS

Atypical GHIS patients, with relatively normal facial appearance, demonstrate less height defect and biochemical abnormalities compared to classical patients. GH insensitivity may be present in children with short stature and an otherwise normal appearance.

Insulin lispro versus regular insulin in children with type 1 diabetes on twice daily insulin

OBJECTIVE

The aim of this study was to compare the clinical efficacy and safety of insulin lispro with regular insulin in 5- to 10-yr-old prepubertal children on twice daily insulin.

RESEARCH DESIGN AND METHODS

Thirty-five children (16 M, 19 F) completed an open-label randomised crossover study, with each child receiving insulin lispro for 3 months and regular insulin for 3 months in addition to their intermediate-acting insulin. Families were instructed to give regular insulin 30 min before meals and insulin lispro immediately before meals. Glycaemic control was monitored by eight-point blood glucose profiles and six weekly hemoglobin A1cs (HbA1cs) and the frequency and severity of hypoglycaemia was documented.

RESULTS

The endpoint HbA1c after 3 months on insulin lispro (8.33%, SD+/-0.89) was not significantly different to that on regular insulin (8.14%, SD+/-0.77). No significant differences were found in blood glucose levels before or after meals, 2-h postprandial glucose excursions or in blood glucose levels before bed between the treatments. However, blood glucose levels at 3 am were significantly lower on regular insulin than on insulin lispro (mean difference -2.35 mmol/L (95%CI: -3.98, -0.72, p=0.01). There was no significant difference in the frequency of hypoglycaemic episodes between the groups.

CONCLUSIONS

The main advantage of insulin lispro in children on twice daily insulin was found to be its greater convenience, this being achieved without a deterioration in glycaemic control. The higher 3 am blood glucose levels in those on insulin lispro could translate to reduced nocturnal hypoglycaemia in some individuals.

A novel mutation affecting the interdomain link region of the growth hormone receptor in a Vietnamese girl, and response to long-term treatment with recombinant human insulin-like growth factor-I and luteinizing hormone-releasing hormone analogue

A Vietnamese girl with Laron syndrome has been treated with recombinant human insulin-like growth factor-I for 4 yr from age 11.28 yr. Her height SD score increased from -6.3 to -4.7 without acceleration of bone age. Isolated breast development progressed despite pubertal suppression with luteinizing hormone-releasing hormone analogue, which was stopped after 3 yr because of growth deceleration. Facial coarsening was documented with serial photographs. Sequencing and in vitro analysis identified a homozygous base pair substitution in exon 6 of the proband's GH receptor (GHR), which changed amino acid 131 from proline to glutamine (P131Q) and disrupted GH binding. Both the P131Q-mutated human GHR and wildtype (wt) hGHR were transiently expressed in COS-1 cells, as demonstrated by Western blotting, but the P131Q-transfected cells did not bind 125I-hGH. Similarly, FDC-P1 cells transfected with wthGHR bound 125I-hGH with high affinity and proliferated in response to GH, whereas the P131Q hGHR cells did neither. In CHO-K1 cells cotransfected with wthGHR and the Egr-1 promotor linked to a luciferase reporter gene, GH evoked a 2.14 +/- 0.21-fold increase in luciferase activity, but there was no response in the cells carrying the P131Q hGHR mutation. From examination of the crystal structure of the GHR, we suggest that the P131Q mutation disrupts the interdomain link between the extracellular domains of the GHR, causing a conformational change that results in disruption of the GH binding site.

Benign intracranial hypertension and recombinant growth hormone therapy in Australia and New Zealand

Benign intracranial hypertension (BIH) is reported in three children from Australia and one from New Zealand, who were being treated with recombinant human growth hormone (rhGH). Three males and one female, aged between 10.5 and 14.2 y, developed intracranial hypertension within 2 weeks to 3 months of starting treatment. A national database, OZGROW, has been prospectively collecting data on all 3332 children treated with rhGH in Australia and New Zealand from January 1986 to 1996. The incidence of BIH in children treated with growth hormone (GH) is small, 1.2 per 1000 cases overall, but appears to be greater with biochemical GHD (<10 IU ml(-1)), i.e. 6.5/1000 (3 in 465 cases), relative risk 18.4, 95% confidence interval 1.9-176.1, than in all other children on the database. The incidence in patients with Turner's syndrome was 2.3/1000 (1 in 428 cases). No cases in patients with partial GHD (10-20 IU ml(-1)) or chronic renal failure were identified. Possible causative mechanisms are discussed. The authors' practice is now to start GH replacement at less than the usual recommended dose of 14 IU m(-2) week(-1) in those children considered to be at high risk of developing BIH. Ophthalmological evaluation is recommended for children before and during the first few months following commencement of rhGH therapy and is mandatory in the event of peripheral or facial oedema, persistent headaches, vomiting or visual symptoms. The absence of papilloedema does not exclude the diagnosis.

Cytosolic autoantigens in lymphocytic hypophysitis

Lymphocytic hypophysitis was first recognized postmortem, then by biopsy, but detection of antipituitary autoantibodies by immunofluorescence has proved unsatisfactory. Immunoblotting has the dual advantages of increased specificity and identification of the mol wt of autoantigens. Sera from 115 patients and 52 normal subjects were immunoblotted against human autopsy pituitary cytosolic proteins. Among the neurosurgical cohort (30), 10 patients had biopsy-proven lymphocytic hypophysitis, and 20 had hypopituitarism secondary to tumor. There were 22 cases with suspected hypophysitis; 47 with either Hashimoto's, Graves', or Addison's diseases; and 15 with rheumatoid arthritis. Antipituitary autoantibodies reactive to a 49-kDa pituitary cytosolic protein were found in 70% of biopsy-proven lymphocytic hypophysitis, 55% of suspected hypophysitis, 42% of Addison's disease, 20% of pituitary tumors, 15% of patients with thyroid autoimmunity, 13% of rheumatoid arthritis patients, and 9.8% of normal subjects. Reactivity to a 40-kDa cytosolic protein was also found in 50% of patients with biopsy-proven disease. These 49- and 40-kDa autoantigens are conserved across species and are not exclusive to pituitary tissue. Immunoblotting has demonstrated antipituitary autoantibodies to 49- and 40-kDa cytosolic proteins in biopsy-proven cases of lymphocytic hypophysitis.

Arginine vasopressin in Cushing's disease

Bilateral simultaneous blood samples were taken from the inferior petrosal sinuses of nine patients with Cushing's disease for measurement of adrenocorticotropin (ACTH), vasopressin (AVP), prolactin, growth hormone, luteinising hormone (LH), and follicle stimulating hormone (FSH). Inter-sinus gradients for ACTH (range 3.3-18.2) and AVP (2.0-375) correctly lateralised the microadenoma in seven of these patients. One additional patient showed an increased gradient for AVP but not ACTH on the side of the tumour. The correlation between the AVP and ACTH concentrations in the petrosal sinus draining the microadenoma was significant. Petrosal sinus plasma concentrations of prolactin and growth hormone were also significantly higher on the side of the tumour than on the non-tumour side. Evidence against a non-specific tumour effect on the secretion of all pituitary hormones was the fact that in most cases the gradients for LH and FSH were not significant. It is proposed that increased delivery of AVP to part of the pituitary may result from an aberrant blood supply, and that AVP may interact with corticotropin releasing factor to promote tumour growth and ACTH release.

Inferior petrosal sinus sampling in acromegaly

In view of the diagnostic value of bilateral simultaneous inferior petrosal sinus sampling (BSIPSS) in localising preoperatively the site of the microadenoma in pituitary dependent Cushing's disease, the clinical value of BSIPSS was evaluated in five acromegalic patients with equivocal or negative pituitary CT scans. Intersinus GH gradients were obtained for all patients (range 1.6-4.2) but in only one case was the gradient correctly localised to the side of the tumour. Gradients of several other pituitary hormones, particularly prolactin (range 1.6-4.0), also demonstrated gradients parallel to the GH intersinus gradients. Despite the paradoxical intersinus GH gradients, the surgeon was able to readily identify the tumour at the time of surgery. Thus BSIPSS is of little assistance to the surgeon for the preoperative radiological evaluation in acromegaly and these results caution against the universal adoption of the BSIPSS technique in the radiological assessment of all secretory pituitary microadenomas.

Fenfluramine increases insulin action in patients with NIDDM

These studies examined the effect of fenfluramine on insulin action and insulin secretion in healthy subjects and patients with non-insulin-dependent diabetes mellitus (NIDDM). In the first study, a double-blind crossover design was used in healthy subjects to compare the effect of short-term fenfluramine therapy (60 mg orally for 3 days) with placebo. Insulin secretion and whole-body insulin sensitivity (determined by frequently sampled intravenous glucose tolerance tests with analysis by the minimal-model method) were unchanged by fenfluramine. In the second study, involving patients with NIDDM inadequately controlled on submaximal to maximal doses of oral hypoglycemic agents, a double-blind crossover strategy was used to compare baseline studies (conducted after a run-in period) with fenfluramine (60 mg orally) or placebo for 4 wk. There was a significant fall in fasting blood glucose after therapy with fenfluramine compared with the baseline study period (13.0 +/- 1.2 vs. 8.4 +/- 0.89 mM, mean +/- SE, P less than .01) with no significant fall in fasting serum insulin (20 +/- 2 vs. 24 +/- 3 microU/ml) or C-peptide (1.3 +/- 0.2 vs. 1.3 +/- 0.1 nM). During euglycemic-hyperinsulinemic (1 mU.kg-1.min-1) clamp studies there was a significant increase in insulin action from 12.7 +/- 2.3 to 17.3 +/- 1.8 min-1.10(3) microU.ml-1 (P less than .05), although clamp insulin levels were lower after fenfluramine treatment (136 +/- 14 vs. 96 +/- 9 microU/ml, P less than .02), reflecting an enhanced metabolic clearance rate for insulin (12.7 +/- 1.5 vs. 20.1 +/- 2.1 ml.kg-1.min-1, P less than .025).(ABSTRACT TRUNCATED AT 250 WORDS)

Combination chemotherapy for adrenal carcinoma: response in a 5 1/2-year-old male

Adrenocortical carcinoma is an uncommon tumor of childhood, and systematic studies of therapeutic options are not available. Children with very large tumours have a poor outlook with surgery alone, so that other treatment should be considered, but the literature is unhelpful in suggesting what this should be. In the case reported here, combination chemotherapy, including cisplatinum, gave a well-documented good partial response, suggesting a possible role for adjuvant chemotherapy using such a drug combination.

Multiple pituitary hormone gradients from inferior petrosal sinus sampling in Cushing's disease

Pre-operative bilateral simultaneous inferior petrosal sinus sampling with assessment of ACTH levels in the left and right sinuses and the periphery was performed in 9 patients with pituitary dependent Cushing's disease who were subsequently found at surgery to have basophil microadenomata. The novel observation of this study was the pattern of secretion of other pituitary hormones so that significant inter-sinus gradients greater than or equal to 1.4:1 were seen for beta-endorphin (2.8 +/- 1.3, mean +/- SEM), PRL (4.2 +/- 1.3) and GH (6.9 +/- 2.4) as well as for ACTH (5.1 +/- 1.1). There was no inter-sinus gradient for LH, FSH and TSH. In these 9 patients with adenomata, the correlations between the inter-sinus gradients for ACTH and beta-endorphin were r = 0.95 (P less than 0.01), ACTH and PRL r = 0.90 (P less than 0.01) and for ACTH and GH r = 0.89 (P less than 0.05). This close association between the gradients for ACTH and other anterior pituitary hormones could be due either to co-secretion of beta-endorphin, PRL and GH by the ACTH-producing pituitary adenomata or to a paracrine effect of beta-endorphin from the tumours on adjacent pituitary tissue. By reflecting the central pituitary hormone milieu, petrosal sinus sampling can give information about pituitary function unobtainable from peripheral hormone levels.

Hormonal and metabolic changes during hypothermic coronary artery bypass surgery in diabetic and non-diabetic subjects

Hormonal and metabolic responses to hypothermic coronary artery bypass grafting (CABG) were studied in three groups: 8 non-diabetic patients, 8 patients with non-insulin-dependent diabetes mellitus (NIDDM) given a glucose pump priming solution and 8 NIDDM patients given a non-glucose infusion. There were no significant differences in stress hormone responses between NIDDM and non-diabetic patients, with adrenaline concentrations rising 10-fold, noradrenaline 4-fold and cortisol 2 to 3-fold. Glucagon rose significantly during bypass only in the NIDDM patients who did not receive a glucose prime. Comparable marked hyperglycaemia was seen in both glucose primed groups during bypass and exclusion of glucose from the prime in NIDDM patients prevented this major rise. Postoperatively, the rise in insulin in the glucose primed NIDDM patients contrasted with the slower rise in the non-glucose primed NIDDM patients who were also hyperglycaemic by this stage. Perioperative hyperglycaemia in NIDDM patients undergoing CABG can be prevented by using a non-glucose priming solution and by giving insulin infusion, particularly postoperatively.