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N N Chan

Publications and source records attributed to N N Chan.

52 records · Page 3Linked to original sources

Metformin-associated lactic acidosis: a rare or very rare clinical entity?

AIMS: Lactic acidosis is a well recognized complication of biguanide therapy which is potentially serious. Although the prevalence of metformin-associated lactic acidosis (MALA) is much lower than that associated with phenformin, it is still being reported sporadically which raises concerns for the practising clinicians. We review the currently available world-wide data of the prevalence of MALA, the risk factors for its development and the current practical guidelines on the use of metformin to minimize the risk of this potential hazard. METHODS: An extensive literature search was conducted from both Medline and Ovid (1965-98) using the following keywords: 'Type 2 diabetes mellitus', 'oral hypoglycaemic drugs', 'biguanides', 'metformin-associated lactic acidosis' and 'renal impairment'. RESULTS: MALA was found to be a very rare clinical entity, being 20 times less common than phenformin-associated lactic acidosis. Amongst all the risk factors, renal impairment appears to be the major precipitating factor for the development of MALA in metformin-treated patients. We also found cases of MALA where no precipitating factors were identified and the underlying mechanism in these cases remains unclear. Practical recommendations of metformin use to minimize the risk of MALA have been listed based on previous reports. CONCLUSIONS: The low prevalence of MALA is comparable to the prevalence of sulphonylurea-induced hypoglycaemia. Metformin has many beneficial metabolic effects in the management of Type 2 diabetes mellitus. Provided that the recommended guidelines for metformin use are strictly adhered to, its widespread use would be safe and the incidence of MALA will be further reduced.

Acidosis, Lactic↗

Lack of response to octreotide in Cushing's syndrome due to metastatic adrenocortical carcinoma.

Functional metastatic adrenocortical carcinoma is an uncommon cause of Cushing's syndrome, which rarely responds to conventional treatment. A patient presenting with Cushing's syndrome secondary to adrenocortical carcinoma underwent surgical resection. Postoperatively, she developed metastatic disease resistant to conventional chemotherapy. Octreotide, a somatostatin analogue which is effective in the treatment of several types of neuroendocrine tumour, was tried to ameliorate her secretory symptoms, but without any therapeutic effect.

Adrenocortical Carcinoma↗

Aldosterone excess: a rare non-nephrophathic cause of hypertension in type I diabetes.

The aetiology of hypertension in type 1 diabetes is commonly due to the presence of diabetic nephrology. A rare case of hypertension in a patient with type 1 diabetes and no proteinuria is reported, where the investigation of borderline hypokalaemia allowed us to make a diagnosis of hyperaldosteronism due to bilateral adrenocortical hyperplasia. Secondary causes of hypertension should always be considered in all diabetic patients, particularly in the absence of clinical proteinuria.

Adrenal Glands↗