Very late stent thrombosis after implantation of drug eluting stent

A case of late stent occlusion of a Sirolimus eluting Cypher stent (Cordis, Johnson and Johnson) presenting as acute ST elevation myocardial infarction 22 months after deployment is reported. The possible mechanisms are discussed.

TB and DOTS: a human rights perspective

Health and human rights are inextricably linked. Factors that violate human rights are likely to result in deprivation and ill-health. TB leads to disability and death thus negatively impacting human rights, more so in poor and marginalised groups. On the other hand DOTS strategy as exemplified by India's TB control programme serves to protect human rights by increasing political commitment, equitable access to quality services and enhancing accountability. By adequate treatment and cure of TB patient, it not only serves the individual but also community by preventing spread and emergence of resistance to available drugs.

Cerebral edema in diabetic ketoacidosis

Cerebral edema is the most important complication of diabetic ketoacidosis in children. It has a high mortality rate of 20 to 90% in different series. Twenty to 40% of survivors suffer from neurologic sequelae. The pathogenetic mechanisms are still controversial and the risk factors which are thought to predict its occurrence do not consistently correlate with cerebral edema in various studies. Prevention and recognition of early warning signs, such as decreased arousal, lethargy after initial improvement, headache, vomiting, relative bradycardia and relative hypertension, are crucial. Therapeutic guidelines to prevent cerebral edema in diabetic ketoacidosis include slow rehydration over about 48 hours, avoidance of hypotonicity and of unnecessary alkali therapy. Early recognition of cerebral edema and prompt institution of hypertonic therapy with mannitol may prevent permanent neurological sequelae.

Quality of life and gender role behavior in disorders of sexual differentiation in India

OBJECTIVE

Culture-specific tools to assess longterm psychosocial outcomes for patients with disorders of sexual differentiation are scant. We conducted a study to develop tools for evaluating gender role behavior and health related quality of life for Indian adolescent patients with intersex disorders. We also studied factors important to parents while deciding sex of rearing for their baby.

METHODS

A 29-item gender role behavior questionnaire and an 18-item health related quality-of-life questionnaire were administered to 82 healthy controls, 13 patients with intersex disorders and 18 patients with type 1 diabetes mellitus. Internal consistency was checked by Cronbach's alpha and test-retest reliability using intra-class correlation coefficient. Responses of 28 parents to a questionnaire on factors affecting the decision of sex of rearing were recorded on a 5-point Likert scale in order of importance.

RESULTS

Cronbach's alpha was 0.92 and 0.75, and intra-class correlation coefficient 0.76 and 0.75, for the gender role behavior and quality-of-life questionnaires respectively, indicating a high degree of internal consistency and stability. The mean composite scores for healthy girls on the gender role behavior questionnaire (82.5 +/- 8.7) differed significantly from that for healthy boys (53.2 +/- 7.1, p <0.001). Factors important to parents while making decisions for sex of rearing were appearance of the genitalia, medical advice, ability to bear children and economic independence.

CONCLUSIONS

We have created valid tools to study gender role behavior and quality of life in adolescent patients with intersex disorders in India. We have also identified in a quantitative way the factors of greatest importance to parents while deciding sex of rearing. These results have direct utility in the management of patients with intersex disorders in India and other similar cultures.

Predictive value of arterial ammonia for complications and outcome in acute liver failure

BACKGROUND AND AIMS

In acute liver failure (ALF), the brain is exposed to high levels of ammonia. Human studies defining the clinical significance of ammonia in ALF are lacking. This prospective study evaluated the relationship of arterial ammonia levels at admission to complications and survival among patients with ALF.

METHODS

Eighty consecutive ALF patients admitted from March 2001 to December 2003 were followed up until death or complete recovery. All had arterial ammonia estimation at admission (enzymatic method). Logistic regression analysis was performed to identify independent predictors of mortality.

RESULTS

Forty two (52.5%) patients died. Non-survivors had significantly higher median ammonia levels than survivors (174.7 v 105.0 micromol/l; p<0.001). An arterial ammonia level of > or = 124 micromol/l was found to predict mortality with 78.6% sensitivity and 76.3% specificity, and had 77.5% diagnostic accuracy. Patients with higher ammonia levels also developed more complications, including deeper encephalopathy (p = 0.055), cerebral oedema (p = 0.020), need for ventilation (p<0.001), and seizures (p = 0.006). Logistic regression analysis showed that pH, presence of cerebral oedema, and arterial ammonia at admission were independent predictors of mortality (odds ratios 6.6, 12.6, and 10.9, respectively). Incorporating these variables, a score predicting mortality risk at admission was derived: 2.53 + 2.91 ammonia + 2.41 oedema + 1.40 pH, where ammonia is scored as 0 (if <124 micromol/l) or 1 (if > or =124 micromol/l); oedema is scored as 0 (absent) or 1(present); and pH is scored as 1 (if < or =7.40) or 0 (if >7.40). Levels of partial pressure of ammonia were equally correlated with outcome.

CONCLUSION

Arterial ammonia at presentation is predictive of outcome and can be used for risk stratification. Ammonia lowering therapies in patients with ALF should be evaluated.

Validation and reproducibility of a food frequency questionnaire to assess energy and fat intake in affluent north Indians

BACKGROUND

India is currently witnessing a sharp rise in noncommunicable disorders such as obesity, diabetes, hypertension and cardiovascular diseases. This rise can be related in part to dietary changes such as increased intake of calories, fat (especially saturated fat) and cholesterol. A simple, accurate and reproducible method to measure these nutrients is essential to study the role of diet in these diseases in epidemiological studies. We aimed to develop and validate a food frequency questionnaire that could be used for this purpose.

METHODS

Thirty urban north Indian subjects (age 23-64 years, 16 men) belonging to a high socioeconomic group were studied. The subjects were selected consecutively over a period of 3 weeks from among those participating in an epidemiological survey on cardiovascular risk factors in an affluent population. A 102-item food frequency questionnaire was developed to capture the intake of calories, fat, saturated fat and cholesterol. The results obtained by the food frequency questionnaire were compared with a 5-day diet record. To assess the reproducibility of the food frequency questionnaire, it was re-administered after 3 months to the 23 subjects available.

RESULTS

It took the dietician 20 minutes or less to administer the questionnaire. There was good correlation between the nutrient values as calculated by the food frequency questionnaire and 5-day diet record. The correlation for energy intake was 0.80, and varied between 0.55 and 0.69 for unadjusted intake of other nutrients. After adjusting for calories, the correlation varied between 0.45 and 0.68. In general, the food frequency questionnaire overestimated the energy-adjusted nutrient intake by 6%-17%. When intake was classified into quartiles, there was good agreement between the two methods: 43%-100% for calories; 29%-86% for other nutrients for unadjusted intake; 29%-71% for nutrients after energy adjustment. On calculation of intake after re-administration of the food frequency questionnaire, there was a moderate to strong correlation (energy adjusted r=0.49-0.90) between the two evaluations for various nutrients.

CONCLUSION

The food frequency questionnaire developed for the assessment of nutrient intake in a north Indian population was easy to administer, showed moderate to good correlation with the 5-day diet record and was reproducible.

Condom-promotion programme among slum-dwellers in Chandigarh, India

This study describes high-risk behaviour and condom usage in inhabitants of an urban slum in the Union Territory of Chandigarh, which has a population of about 20,000. A cohort of 375 participants was followed-up before and after an intervention. Half of the married but only one-eighth of the unmarried slum dwellers were using condoms regularly. One-quarter of the study subjects practised high-risk behaviour and this was higher among unmarried (44.88%) than married participants (18.7%). An intervention involving education on condom use and provision of free condoms increased the condom usage rate from 31.73% in the pre-intervention phase to 60% in the postintervention phase.

Percutaneous closure of iatrogenic femoral arteriovenous fistula using endovascular covered stent

Local complications after femoral arterial catheterization, such as hematomas, pseudoaneurysms, arteriovenous fistulas (AV fistulas), and arterial occlusions, are becoming more common, with the growing number of complex invasive procedures being undertaken, especially in older and sicker patients. Newer percutaneous techniques are being developed to treat these. Covered stents are an effective, safe, and less invasive way to deal with pseudoaneurysms and AV fistulas. This case report highlights the application of this technique to treat an iatrogenic femoral AV fistula in a 69 years male.

Effect of stepwise reduction in minute ventilation on PaCO2 in ventilated newborns

OBJECTIVE

To study the effect of step reduction of expired minute ventilation (MV) on PaCO2 in ventilated newborns and to determine whether MV within a defined range can predict PaCO2.

DESIGN

Prospective descriptive.

SETTING

Referral neonatal unit of a teaching hospital.

METHODS

Forty neonates stable on mechanical ventilation receiving minute ventilation in the range of 150-210 ml/kg/min. were studied. The spectrum of disorders for which the babies were ventilated included apnea of prematurity in 16, pneumonia in 14, meconium aspiration syndrome in 6 and hyaline membrane disease in 4. Median age at study was 6 days and median weight at study was 2.1 kgs. The MV was reduced from 210 to 150 mL/kg/min in three steps and concomitant PaCO2 was measured. Reductions were not done if PaCO2 was more than 50 mmHg. MVs were plotted against PaCO2 and a regression equation to predict PaCO2 from MV was calculated.

RESULTS

A stepwise increase was seen in CO2 with reduction of MV over the range studied. The median MV and median PaCO2 achieved in the three steps were 201 mL/kg/min and 36.7 mm of Hg, 180 mL/kg/min and 41.7 mm of Hg, 160 mL/kg/min, and 44.3 mm of Hg. The regression equation to predict PaCO2 was PaCO2 = 70 - 0.17 x MV in mL/kg/min, r = -0.45, r2 = 0.20, residual variance (s2) = 39.37; gave a predicted PaCO2 within 12.5 mmHg. for a given MV.

CONCLUSION

Reducing minute ventilation led to an increase in the levels of PaCO2. Minute volumes of 160 ml/kg/min correlated with PaCO2 value of 44.3 mm of Hg. MV as low as 160 mL/kg/min are well tolerated by newborns.

Etiology and outcome of childhood and adolescent diabetes mellitus in North India

The etiology of childhood onset diabetes mellitus (DM) varies between regions and races, and its long-term outcome is affected by social and economic factors. There are scant data on the etiology of childhood DM and outcome of multidisciplinary team management from developing countries. We retrospectively analyzed case records of 160 predominantly middle socio-economic group patients with onset of DM < or =18 years of age for etiology and features at presentation. In addition, we prospectively studied acute and chronic complications and metabolic control in a subset of 67 patients. Type 1 DM comprised 81%, type 2 DM 8%, and fibrocalculous pancreatic DM 9% of patients. Mean HbA1c was 8.0+/-1.5%. Retinopathy was present in 22% and nephropathy in 18% of those with DM duration > or =5 years (mean age 21.2+/-6.8 years, mean duration 10.2+/-4.6 years). The frequency of ketoacidosis and severe hypoglycemia was 5.0 and 3.3 episodes per 100 patient years. Mortality was 7% over 823 person years of follow up. We conclude that fairly good metabolic control is achievable in a middle socio-economic population in India, with the assistance of a diabetes education program. The frequency of microvascular complications is comparable to that in the literature. However, mortality remains unacceptably high.

Drug-eluting stents: new era and new concerns

At present there is much excitement about drug-eluting stents, which hold promise for the treatment of coronary artery disease. This ingenious therapy involves coating the outside of a standard coronary stent with a thin polymer containing medication that can prevent scarring at the site of coronary intervention. Early trials with sirolimus coated stents showed that they might prevent coronary artery restenosis, but later studies, involving more complex coronary lesions, did not show a complete absence of restenosis. Recent studies have demonstrated the long term cost effectiveness of drug-eluting stents as they have reduced the need for revascularisation procedures. At present there are few data on the safety and effectiveness of stents over follow up periods exceeding two years, and data obtained from animal models of stenting might not be completely applicable to humans. There are concerns that drug-eluting stents might delay, rather than inhibit, restenosis. Also there is concern regarding the inflammation caused by the polymer substrate. This article reviews the present data on drug-eluting stents and their benefits, shortcomings, and concerns.

Vulnerable plaques, inflammation and newer imaging modalities

Currently, inflammation is considered to be the central player in the pathogenesis of atherosclerosis. It leads to the formation of multiple plaques in the arterial beds including coronary vasculature. Recent studies using the latest imaging techniques have shown that in patients with acute coronary syndromes (ACS) multiple plaques are ruptured and have thrombus formation on them. Various factors make these plaques unstable, these include structural components of plaque like thin fibrous cap, high lipid content of the plaque core and inflammation, both localized and generalized. It has been shown that most of the ACS are caused by plaques causing non-critical stenosis as seen on traditional X-ray angiography. Also, the phenomenon of remodelling makes angiography a poor technique for plaque visualization. Hence newer modalities are required to identify these "vulnerable plaques". Intravascular ultrasound (IVUS), thermography and Magnetic Resonance Imaging (MRI) are a few such promising techniques. Here we review the invasive and non-invasive modalities that can be helpful in the identification of these plaques before they become unstable and cause ACS, and also the available therapies to stabilize these plaques.

Varying role of vitamin D deficiency in the etiology of rickets in young children vs. adolescents in northern India

The relative importance of calcium vs. vitamin D deficiency in the etiology of nutritional rickets in the tropics may be different in children compared with adolescents. We studied calcium intake, sun exposure, serum alkaline phosphatase, and 25 hydroxyvitamin D in 24 children and 16 adolescents with rickets/osteomalacia. The values were compared with those obtained in control subjects (34 children and 19 adolescents). We found that young children with rickets had lower calcium intake compared with controls (285 +/- 113 vs. 404 +/- 149 mg/day, p < 0.01), but similar sun exposure (55 +/- 28 vs. 56 +/- 23 min x m2/day) and 25 hydroxyvitamin D (49 +/- 38 vs. 61 +/- 36 nmol/l). Sixteen of 24 children with rickets had 25 hydroxyvitamin D above the rachitic range (> 25 nmol/l), in contrast to one of 16 adolescents. Adolescent patients had low calcium intake vs. controls (305 +/- 196 vs. 762 +/- 183 mg, p < 0.001), and lower sunshine exposure (16 +/- 15 vs. 27 +/- 17 min x m2/day, p < 0.01) and serum 25 hydroxyvitamin D (12.6 +/- 7.1 vs. 46 +/- 45.4 nmol/l, p < 0.001). The odds ratio for developing rickets with a daily calcium intake below 300 mg was 4.8 (95 per cent CI, 1.9 - 12.4, p = 0.001). Subjects with rickets were randomized to receive 1 g calcium daily, with or without vitamin D. Children showed complete healing in 3 months, whether they received calcium alone or with vitamin D. Adolescents showed no response to calcium alone, but had complete healing with calcium and vitamin D in 3-9 months (mean 5.3 months). Thus deficient calcium intake is universal among children and adolescents with rickets/osteomalacia. Inadequate sun exposure and vitamin D deficiency are important in the etiology of adolescent osteomalacia.

Cardiac resynchronization therapy in heart failure: recent advances and new insights

Newer non-pharmacological therapies for heart failure are being evaluated for patients of congestive heart failure (CHF). Mechanical support with left ventricular assist devices and heart transplantation are reserved for the minority of patients who have severely decompensated heart failure. Despite these therapeutic advances, it is generally accepted that current therapies do not adequately address the clinical need of patients with heart failure, and additional strategies are being developed. Cardiac resynchronization therapy (CRT) is a new modality that involves synchronization of ventricular contraction and has shown a lot of promise in managing symptomatic patients of CHF who are on optimal medical therapy and have interventricular conduction delay (IVCD). It has improved exercise tolerance and NYHA functional class in such patients in sinus rhythm and a recent meta-analysis has also shown mortality benefits in CHF. Recently benefits of CRT have also been observed in CHF patients who do not have wide QRS complexes on electrocardiogram (EKG). It has also been shown to benefit drug refractory angina in CHF. Recent studies have also focused on the combined use of CRT and implantable cardioverter defibrillator (ICD) and it has shown encouraging results. Our aim in this descriptive review is to define practice guidelines and to improve clinicians' knowledge of the available published clinical evidence, concentrating on few randomized controlled trials.

Aetiology and clinical profile of osteomalacia in adolescent girls in northern India

BACKGROUND

The adolescent age group is particularly prone to nutritional rickets/osteomalacia due to an increased demand for nutrients, especially calcium and vitamin D. Osteomalacia presents with non-specific signs and symptoms because of which diagnosis may be delayed. Vitamin D deficiency is unexpected in India, which is a tropical country with abundant sunshine.

METHODS

We prospectively studied the clinical presentation, aetiology and social factors contributing to adolescent rickets/ osteomalacia in our region.

RESULTS

We saw 21 symptomatic adolescents with osteomalacia during the study period (November 2000-July 2002). All were girls. Only 1 practised purda and 4 belonged to a low socioeconomic class. The mean (SD) duration of illness before correct diagnosis was 2.8 (2.1) years. Bone pains and muscular weakness were universally present. Non-specific complaints (especially limb pains being mistaken for joint involvement) led to a delay in diagnosis with consequent morbidity. All but 1 patient had low serum 25-hydroxyvitamin D levels (<10 ng/ml), with the mean (SD) being 4.9 (2.7) ng/ml. Their mean dietary calcium intake was low 1265 (199) mg/day, range 40-810 mg/day]. Restricted outdoor activities (n = 19) and the traditional dress code (n = 21) were contributory factors, as they led to poor exposure to sunshine.

CONCLUSIONS

Nutritional osteomalacia among adolescents is a poorly recognized entity. Even in non-purda practising communities in the tropics, poor exposure to sunshine due to social factors, compounded by low dietary calcium intake, can lead to osteomalacia in adolescents.