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Objective For ‘asymptomatic carriers’ of the succinate dehydrogenase subunit B (SDHB) gene mutations, there is currently no consensus as to the appropriate modality or frequency of surveillance imaging. We present the results of a surveillance programme of SDHB mutation carriers. Design Review of clinical outcomes of a surveillance regimen in patients identified to have a SDHB gene mutation, based on annual MRI, in a single UK tertiary referral centre. Patients A total of 92 patients were identified with an SDHB gene mutation. 27 index patients presented with symptoms and 65 patients were identified as asymptomatic carriers were identified. Measurements Annual MRI of the abdomen, with alternate year MRI of the neck, thorax and pelvis. Presence of an SDHB-related tumour included paraganglioma (PGL), phaeochromocytoma (PCC), renal cell carcinoma (RCC) and gastrointestinal stromal tumour (GIST). Results 43 PGLs, 8 PCCs and 1 RCC occurred in the 27 index patients (23 solitary, 4 synchronous, 5 metachronous). A further 15 SDHB-related tumours (11 PGLs, 3 RCCs, 1 GIST) were identified in the asymptomatic carriers on surveillance screening (25% of screened carriers); 10 on the first surveillance imaging and five on subsequent imaging 2-6years later. 11 patients had malignant disease. Conclusions SDHB-related tumours are picked up as early as two years after initial negative surveillance scan. We believe the high malignancy rate and early identification rate of tumours justifies the use of 1-2 yearly imaging protocols and MRI based imaging could form the mainstay of surveillance in this patient group thereby minimising radiation exposure. This article is protected by copyright. All rights reserved.

Positron emission tomography (PET) with 18F-fluorodeoxy-glucose indicates metabolically active tissue. When investigating enhancing intracranial tumours, we have suggested that PET positivity might suggest an intracranial germ cell tumour (IGCT). Here, we present a case with dicentric IGCT where PET was initially discordant between the lesions and where PET then became negative despite clearly aggressive clinical behaviour. A cautionary note is introduced with respect to the interpretation of negative 18F-FDG PET when investigating enhancing intracranial lesions.

BackgroundCabergoline is a dopamine agonist that may be used as primary or adjunctive therapy for acromegaly. Although one study suggested biochemical control may be achieved in a substantial proportion of patients, it is still commonly perceived to be a relatively ineffective treatment.Design and methodA prospective audit was performed of 15 consecutive acromegalic patients (eight males, seven females, median age 55, range 31–92 at presentation) treated with cabergoline to determine the effective dose and tolerability. All had normal anterior pituitary function; two patients had hyperprolactinaemia. Magnetic resonance imaging revealed nine adenomata, two partially empty sellae and four structurally normal pituitary glands. Nine patients had undergone transsphenoidal surgery 1–12 months, and one patient had received pituitary radiotherapy 18 years, prior to commencement of cabergoline. All patients had biochemical GH excess; median serum IGF1 471 ng/ml, range 239–746 ng/ml. The calculated mean of a series of GH measurements ranged from 2.7–45.8 mIU/l, median 9.7 mIU/l.ResultsOn a median weekly dose of cabergoline of 1.75 mg (range 0.5–7 mg) normalisation of both IGF1 and GH occurred in 4 out of the 15 patients (27%). Out of the 15 patients (33%), 5 achieved a serum IGF1 within the reference range with notable reductions seen in a further five patients. Nine patients (60%) achieved a mean serum GH level of less than 5 mIU/l. Duration of treatment was 2–52 months and was well tolerated in 14 patients.ConclusionCabergoline can be an effective and well tolerated primary or adjunctive therapy for acromegaly and useful clinical responses are noted even with modest doses.

In many countries, treatment of childhood-onset GH deficiency (GHD) with GH ceases when linear growth is complete. Peak bone mass occurs several years after the completion of linear growth. Given that GH has important anabolic actions on bone, discontinuation of GH therapy at the completion of linear growth may have adverse consequences for the attainment of peak bone mass in adolescent GHD patients. In this United Kingdom multicenter study, 24 adolescents (13 males, mean age 17.0 +/- 1.4 yr, SD) with severe GHD were randomized to discontinue or continue GH (0.35 IU/kg x wk) at the completion of linear growth. Whole body bone mineral content (BMC) and lumbar spine bone mineral density were assessed by dual-energy x-ray absorptiometry at baseline and then at 6-month intervals for 1 yr. Markers of bone remodeling (serum bone-specific alkaline phosphatase and urinary deoxypyridinoline) were measured at the same time points. In patients who continued GH (GH+), median BMC increased by 3.8% (interquartile range, 2.6, 5.9, P < 0.001) at 6 months; and by 6.0% (3.7-9.1, P < 0.001) at 12 months. In patients who discontinued GH (GH-) median BMC was unchanged at 6 and 12 months (+1.9%, -0.4-4.2, P = 0.9; and +2.4%, 0.4-4.9, P = 0.5, respectively, median, interquartile range). The differences in median change in BMC between the two groups at 6 and 12 months was marginally significant (P = 0.085 and 0.074, respectively). Mean lumbar spine bone mineral density increased by 4.7 (95% confidence interval, 1.0, 8.2) at 12 months in patients continuing GH (P = 0.01), but the mean change was not statistically significant change in patients who discontinued GH [+2.7% (95% confidence interval, -0.8, +6.2)]. These preliminary data suggest that, in adolescent patients with severe GHD, discontinuation of GH at completion of growth may limit the attainment of peak bone mass in this patient group. This may predispose to clinically significant osteopenia in later adult life.

Summary objective Suprasellar germ cell tumours are rare, and there are few series of patients outlining the problems in diagnosis and management, and providing clear guidelines for optimal therapy. We have therefore reviewed our own series of 11 such patients who were managed in a joint endocrinology/clinical oncology setting. patients and design A retrospective case review assessment of all patients seen within a given time. Clinical, biochemical and radiological findings were reviewed, the types of therapy administered noted, and the responses to treatment analysed. results In the years 1977–2001, 11 patients with suprasellar (SS) germ cell tumours (GCT) were seen (germinomatous : nongerminomatous = 8 : 3). SSGCT had an approximately equal sex incidence (M : F, 6 : 5), in contrast to pineal tumours, the commonest site of origin of intracranial GCT and which occur predominantly in men. The median age at presentation was 20 years (range 6–49 years) with a median duration of symptoms before diagnosis of 17 months (range 1–35 months). Polyuria was the commonest presenting symptom (10 patients). Diabetes insipidus occurred in all patients, as did partial or complete anterior pituitary failure. Visual failure was present in 55% of cases. Anorexia, weight loss and disturbed thirst sensation were also common. Positron emission tomography scanning was occasionally useful in the evaluation of suprasellar tumours/pituitary stalk lesions deemed too risky to biopsy. A ‘central nervous system-friendly’ chemoradiotherapy regimen comprising vincristine, etoposide and carboplatin and differential daily dose irradiation, usually administered using a partial transmission block technique, produced a 5-year survival of 100% with low morbidity. Treatment did not correct previously abnormal endocrine function although it did improve vision in three of six patients. conclusions We therefore emphasize the use of techniques other than biopsy in the diagnosis of these patients, note the problems in the management of their fluid control, and highlight the favourable response to a combined chemotherapy-radiotherapy protocol.

OBJECTIVE—Monozygotic twins are usually discordant (only one twin affected) for type 1 diabetes. Discordance for disease between such twins implies a role for nongenetically determined factors but could also be influenced by a decreased load of diabetes susceptibility genes. The aim of this study was to determine whether two susceptibility genes were less prevalent in discordant twins compared with concordant twins. RESEARCH DESIGN AND METHODS—We studied 77 monozygotic twin pairs (INS), 40 concordant and 37 discordant, for type 1 diabetes at polymorphism of the insulin gene region on chromosome 11p and HLA-DQBI. RESULTS—The disease-associated INS genotype (Hph I) was identified in 87.5% of the concordant twins but only in 59.5% (P = 0.005) of the discordant twins. Neither DQB1*0201 nor DQB1*0302 was seen in 2 of 40 (5%) concordant twins compared with 8 of 37 (22%) discordant twins (P = 0.04). No statistical differences were seen between concordant and discordant twins at individual alleles of DQB1. Combining insulin and DQ data, 5% of concordant twins compared with 32.4% of discordant twins had neither DQB1*0201/DQB1*0302 nor the high-risk Hph I INS “++” genotype (P = 0.002). CONCLUSIONS—We conclude that the possession of the high-risk Hph I insulin genotype increases the likelihood of identical twins being concordant for type 1 diabetes and that the “load” of both major histocompatibility complex (MHC) and non-MHC susceptibility genes has an impact on the disease penetrance of type 1 diabetes.

Insulin dependent diabetes mellitus (IDDM) is an autoimmune disease with a strong association between disease and the HLA class II region. Because abnormal antigen processing, in part characterized by altered class I processing, has been identified in patients with IDDM, the TAP (transporter associated with antigen processing) genes located in the HLA class II region make attractive candidate genes for IDDM. Five coding region variants of TAP1 were typed in a cohort of well characterized Finnish patients with diabetes (n = 119) and compared to racially marched control subjects (n = 92). We found that although no single TAP1 polymorphism was associated with IDDM, a genotypic combination of Ile/Val at codon 333 with Asp/Asp at codon 637 was found more frequently in subjects with IDDM (9.4%) compared to controls (1.2%; p = 0.025). This could not be accounted for by an association with any particular haplotype defined by class I or class II serology.

HLA-DQ gene polymorphism in primary IgA nephropathy in three European populations. MHC Class II genes may contribute to susceptibility to IgA nephropathy (IgAN). We have previously identified a restriction fragment length polymorphism (RFLP) of the DQB1 region that associated with IgAN in British Caucasoids. However, another group, while demonstrating a DQB1 association, was unable to confirm our finding. MHC molecules are heterodimers consisting of an α and β chain, and thus polymorphism of the DQA1 α chain may also be important to disease pathogenesis in IgAN. Therefore, we have determined DQA1 alleles and re-examined DQB1 alleles in British Caucasoids with IgAN using an approach that can differentiate between the common DQ alleles; we have also extended our studies to Caucasoid populations from Northern and Southern Europe, thereby addressing the possibility of variation in genetic susceptibility between populations. DNA was prepared from IgAN patients (British, N = 105; Italian, N = 71; Finnish, N = 48) and healthy controls (British, N = 111; Italian, N = 63; Finnish, N = 41). DQA1 alleles were identified by TaqI RFLP and Southern blotting; alleles that could not be fully resolved by Taq Southern blotting were identified by PCR-RFLP. DQB1 alleles were identified by polymerase chain reaction (PCR) based technique (PCR-RFLP). No consistent association of DQ alleles were found between the populations studied. In British patients a decreased fequency of DQB1*0201 was observed ( P = 0.008), in Finnish patients a decreased frequency of DQB1*0602 was observed ( P = 0.01), and in Italian patients no association between DQ markers and IgAn was found. These data demonstrate population variation in disease association, but no strong or consistent association in the DQ region.

A 53 year old man presented to the emergency department complaining of a two week history of blurry vision, particularly while reading the newspaper and television text. He felt well and denied associated headaches, limb weakness, or slurred speech. His medical history was uneventful and he was not currently taking medication. On examination his respiratory rate was 14 breaths per minute, oxygen saturation was 100% on room air, and vesicular breath sounds on chest auscultation. He had a regular pulse of 80 beats per minute, a hyperdynamic apex beat on palpation, and normal heart sounds were auscultated. The average of several repeated blood pressure measurements were 271/179 mm Hg in the left arm, and 265/183 mm Hg in the right. Electrocardiography showed a combined S wave in lead V1 and R wave in lead V6 of >35 mm, suggestive of left ventricular hypertrophy on voltage criteria. His abdomen was soft, non-tender, and his body mass index measured 30. Visual acuity (pinhole corrected) was 6/36 in the left eye and 6/18 in the right eye. There was a full range of …