Homeostatic model assessment for insulin resistance [HOMA-IR]: a better marker for evaluating insulin resistance than fasting insulin in women with polycystic ovarian syndrome

Objective: To assess the utility of HOMA-IR in assessing insulin resistance in patients with polycystic ovary syndrome [PCOS] and compare it with fasting insulin for assessing insulin resistance [IR]

Study Design: Observational study

Place and Duration of Study: Section of Clinical Chemistry, Department of Pathology and Laboratory Medicine, The Aga Khan University Hospital, Karachi, from January 2009 to September 2012

Methodology: Medical chart review of all women diagnosed with PCOS was performed. Of the 400 PCOS women reviewed, 91 met the inclusion criteria. Insulin resistance was assessed by calculating HOMA-IR using the formula [fasting glucose x fasting insulin]/405, taking normal value <2 in adults and hyperinsulinemia based on fasting insulin levels >/=12 microIU/ml

Results: A total of 91 premenopausal women diagnosed with PCOS were included. Mean age was 30 +/- 5.5 years. Mean HOMA-IR of women was 3.1 +/- 1.7, respectively with IR in 69% [n=63] women, while hyperinsulinemia was present in 60% [n=55] women [fasting Insulin 18.5 +/- 5.8 microIU/ml]. Hyperandrogenism was present in 53.8% [n=49], whereas 38.5% [n=35] women had primary infertility or subfertility, while 65.9% [n=60] had menstrual irregularities; and higher frequencies were observed in women with IR. Eight subjects with IR and endocrine abnormalities were missed by fasting insulin

Conclusion: Insulin resistance is common in PCOS and it is likely a pathogenic factor for development of PCOS. HOMAIR model performed better than hyperinsulinemia alone for diagnosing IR

Tumour induced osteomalacia

Tumour-induced osteomalacia [TIO] is a rare paraneoplastic syndrome usually presenting with bone pain, fracture of bones and muscle weakness. It is caused by high serum levels of fibroblast growth factor 23 [FGF-23], which is a hormone-regulating phosphate, and vitamin D. FGF-23 is secreted by several tumours, especially benign mesenchymal tumours which are very small and difficult to locate. There is a significant delay from onset of symptoms to the diagnosis of this entity due to occult nature of this disease. We present a case of young male who presented with long history of progressively worsening muscular pain and weakness, rendering the patient confined to bed. Our aim of presenting this patient as a case report is to make physicians realise that any patient with unexplained muscular weakness and pain must undergo workup for TIO, including serum phosphate measurement, as this is a rare but potentially curable disease

A case of Gitelman syndrome with severe hyponatraemia and hypophosphataemia

Gitelman syndrome (GS) is a renal tubular disorder of the thiazide-sensitive sodium chloride cotransporter, which is located in the distal tubule of the loop of Henle. We present a rare case of GS complicated by severe hyponatraemia and hypophosphataemia. A 17-year-old boy was admitted to our institution with fever and lethargy. The workup revealed typical features of GS, i.e. hypokalaemia, hypomagnesaemia and metabolic alkalosis. In this report, we discuss the differential diagnoses and rationale for accepting GS as the most likely diagnosis. This case was complicated by severe hyponatraemia (115 mmol/L) and hypophosphataemia (0.32 mmol/L). We concluded that the syndrome of inappropriate secretion of antidiuretic hormones could not be ruled out and that respiratory alkalosis was the most likely aetiology of hypophosphataemia. This case report also generates an interesting discussion on water and electrolyte metabolism.

Frequency of chronic complications of type II diabetes

To assess the frequency of chronic complications of type II diabetes in subjects attending a tertiary care unit in Karachi, Pakistan. Design: A cross-sectional analytical study. Place and Duration of Study: First visit of all type II diabetic subjects attending the outpatient department of Baqai Institute of Diabetology and Endocrinology from September 1996 to December 2001. Subjects and Computerized clinical records of 2199 type II diabetic subjects were analyzed for this study. The clinical and laboratory variables were statistically evaluated with significance at p. Means of glycosylated hemoglobin HbA1c, fasting and random plasma glucose levels, systolic blood pressure, triglycerides and high density lipoproteins [HDL] were higher than the risk indicator value for both genders [p<0.005]. Mean body mass index and total blood cholesterol was higher for females only. Hyperglycemia was present in 88%, high HbA1c in 81%, low HDL in 81%, obesity in 66% and hypertriglyceridemia in 54%, neuropathy in 36%, proteinuria in 28% and hypertension in 50% of the subjects. Frequency of obesity, low HDL and hypertension was higher among females [p<0.001 in each case]. Retinopathy [p<0.05], nephropathy [p<0.005], neuropathy [p<0.005] and foot ulcers [p<0.001] were higher among males. Frequency of obesity was significantly higher among those with shorter duration and in younger group while frequency of other complications was higher among those with longer duration and in the older groups. Higher rates of complications were observed compared to previous studies. Certain variables showed significant association with gender and age as described above