A rare ganglioneuroblastoma secreting dopamine and the value of its measurement in diagnosis and prognosis.

A case is described of a patient with a ganglioneuroblastoma, initially located in the right adrenal, which produced an excess of dopamine (7646 and 7959 nmol/24 h), approximately two and a half times the upper limit of the normal daily urine output. The urinary excretion of noradrenaline, adrenaline and methylated derivatives was always within the normal reference ranges. The patient was generally well, with normal blood pressure and only mild flushes. Two years after surgical resection, recurrence was indicated by an increase in urinary dopamine (8507 nmol/24 h); it was located in the tumour bed and left side of the neck by CT and (123)I MIBG scans. The patient was treated with a high dose of (131)I MIBG, with subsequent reduction in dopamine production. This was repeated on four other occasions, the latest being in January 2005. The output of dopamine was thus used as a marker of tumour diagnosis and progression and it is recommended that the assay of dopamine be included in the screening of catecholamine-secreting tumours to avoid possible misdiagnosis.

An unusual cause of diabetic ketoacidosis and fulminant septicaemia.

BACKGROUND: Diabetic ketoacidosis (DKA) is a common medical emergency. Resistant and recurrent DKA can be due to underlying infection, and a detailed travel history may be important in determining the cause in such cases. We report here a case of unusual DKA and fulminant septicaemia in a Caucasian male with Type 1 diabetes 2 years after returning from living in Thailand. CASE REPORT: A 39-year-old Caucasian male was diagnosed with Type 1 diabetes whilst working in Thailand where he also subsequently developed a cavitating lung lesion diagnosed locally as pulmonary tuberculosis. Two years after returning to the UK he was admitted with DKA and septicaemia. Despite correction of his DKA his condition deteriorated and he developed a fluid collection anterior to the left hip on computed tomography scanning. Blood and fluid aspirate cultures confirmed a diagnosis of melioidosis, a rare fulminant septicaemia in the UK, but endemic in South-east Asia and tropical Australia. Full recovery followed changing antibiotics to intravenous ceftazidime with no relapse 3 years after acute episode. CONCLUSIONS: Physicians as well as microbiologists should consider melioidosis in anyone presenting with septicaemia and/or resistant DKA, especially if the history includes travel to endemic areas or if the cultures suggest Pseudomonas-like organism. With increasing international travel, it is crucial to remember that good travel history could be life-saving in some cases of septicaemia.

A case of severe diabetic retinopathy in pregnancy.

Proliferative retinopathy is a recognized long-term complication of diabetes and the commonest cause of blindness in young people. There is, however, some uncertainty regarding counselling given on the continuation of pregnancy when it is complicated by retinopathy. This case is used to highlight this difficulty and to discuss management based on literature review.

Genetic and metabolic studies in diabetic neuropathy.

Forty-one diabetic patients with symptomatic diabetic neuropathy were studied together with an equal number of matched diabetic subjects without neuropathy. The acetylator status was determined and HLA-A, B, C and DR antigens were investigated. Metabolic control was assessed by measurement of glycosylated haemoglobin and by the mean of multiple random clinic blood glucose values. No significant difference was observed between the two groups in the proportion of fast and slow acetylators. The distribution of HLA frequencies was similar in subjects with and without neuropathy for both Type 1 (insulin-dependent) and Type 2 (non-insulin-dependent) diabetic patients. When compared with diabetic subjects without neuropathy, the neuropathy group had higher levels of both glycosylated haemoglobin (mean +/- SEM: 50.1 +/- 1.4 versus 57.5 +/- 1.8 mmol hydroxymethylfurfural/mol haemoglobin (10.5 +/- 0.3 versus 12.0 +/- 0.4% haemoglobin A1, p less than 0.01) mean blood glucose (9.3 +/- 0.4 versus 11.3 +/- 0.5 mmol/l, p less than 0.005). This study provides no evidence that genetic factors increase the susceptibility of diabetic patients to develop neuropathy. In contrast, the elevated glycosylated haemoglobin and blood glucose levels strengthen the association between hyperglycaemia and diabetic neuropathy.

Dynamic foot pressure and other studies as diagnostic and management aids in diabetic neuropathy.

The pressures and loads under the feet during walking have been compared in three groups of 41 patients each, using a microprocessor-controlled optical system. Group A consisted of patients with diabetic neuropathy, group B of non-neuropathic diabetic patients, and group C of nondiabetic controls. Thirteen patients in group A had a history of neuropathic foot ulceration. Other investigations in the diabetic patients included motor conduction velocity (MCV) in the median and peroneal nerves, vibration perception threshold (VPT) in the great toes, the valsalva response (VR), skin resistance (SR), and the ankle pressure index (API). Fifty-one percent of neuropathic feet had abnormally high pressures underneath the metatarsal heads compared with 17% of the diabetic controls and 7% of nondiabetic subjects. All those feet with previous ulceration had abnormally high pressures at the ulcer sites. Of the other investigations, the VPT correlated most significantly with the presence of foot ulceration. In addition, a low median and peroneal nerve MCV, an abnormal VR, a high API, and the absence of sweating all correlated with the presence of foot ulceration. We therefore conclude that simple bedside investigations, such as measurement of the VPT alone, may be useful in identifying those patients at risk of foot ulceration. Foot pressure studies may then be used in such patients as a predictive and management aid by determining specific areas under the foot that are prone to ulceration.

Elevated glycosylated hemoglobin in diabetic neuropathy.

Glycosylated hemoglobin (GHb) levels were measured in 36 patients with established symptomatic neuropathy and in an identical number of matched controls. Strict criteria were employed in the selection of subjects and all had neuropathy of at least 12 months' duration. The diagnosis of neuropathy was supported by estimation of motor conduction velocities and vibration perception threshold. A semi-automated colorimetric technique, employing the reaction between thiobarbituric acid and 5-hydroxy-methyl furfural, was used for the estimation of GHb. Those patients with neuropathy had significantly higher GHb levels (58.2 +/- 11.3 mmol HMF/mol Hb) than the controls (50.0 +/- 8.9 mmol HMF/mol Hb) (p less than 0.01). This suggests that hyperglycemia or related metabolic abnormalities are important factors in established symptomatic neuropathy.

A comparison study of blood glucose test strips.

Blood glucose test strips provide a convenient and rapid method for estimation of blood glucose. They can be read either by eye against a color scale or in a reflectance meter. This study compares the performance characteristics of the principal test strips available. When read visually, the BM Glycemie 20-800 (Chemstrip bG) strip was shown to be more accurate than the Dextrostix strip. Comparison of the meter systems showed Reflotest-Glucose to be more accurate and precise than Dextrostix. This was because the Reflotest system was read closer to the endpoint of color development and because there was less subsequent color fade than with the Dextrostix system. Reflotest-Glucose and Reflotest-Hypoglycemie developed colors that were stable for at least 2 days after completion of the test. However, when using a reflectance meter the Reflotest system required two strips to cover the important range of blood glucose.

Renal autotransplantation in the treatment of hypertension and uraemia due to renal artery stenosis.

Four cases of renovascular hypertension cured or improved by renal autotransplantation are described. In one case correction of renal ischaemia resulted in an improvement of renal function. Previous reports of this technique are reviewed and the limitations of the more standard operation of saphenous vein bypass graft are discussed.