A randomized trial of two postexposure prophylaxis regimens to reduce mother-to-child HIV-1 transmission in infants of untreated mothers

BACKGROUND: Single-dose nevirapine (NVP) prophylaxis to mother and infant is widely used in resource-constrained settings for preventing mother-to-child transmission (MTCT) of HIV-1. Where women do not access antenatal care or HIV testing, postexposure prophylaxis to the infant may be an important preventative strategy. METHODS: This multicentre, randomized, open-label clinical trial (October 2000 to September 2002) in South Africa compared single-dose NVP with 6 weeks of zidovudine (ZDV), commenced within 24 h of delivery among 1051 infants whose mothers had no prior antiretroviral therapy. HIV-1 infection rates were ascertained at birth, and at 6 and 12 weeks of age. Kaplan-Meier survival methods were used to estimate HIV-1 infection rates in an intention-to-treat analysis. RESULTS: Overall, 6 week and 12 week MTCT probability was 12.8% [95% confidence interval (CI),10.5-15.0] and 16.3% (95% CI,13.4-19.2), respectively. At 12 weeks, among infants who were not infected at birth, 24 (7.9%) infections occurred in the NVP arm and 41 (13.1%) in the ZDV arm (log rank P = 0.06). Using multivariate analysis, factors associated with infection following birth were ZDV use [odds ratio (OR), 1.8; 95% CI,1.1-3.2; P = 0.032), maternal CD4 cell count < 500 x 10(6) cells/l (OR, 2.5; 95% CI,1.3-5.0; P = 0.007), maternal viral load > 50 000 copies/ml (OR, 3.6; 95% CI,2.0-6.2; P < 0.0001) and breastfeeding (OR, 2.2; 95% CI,1.3-3.8; P = 0.006). CONCLUSION: A single-dose of NVP given to infants offers protection against HIV-1 infection and should be a strategy used in infants of mothers with untreated HIV infection.     

Acute Budd-Chiari syndrome with liver failure: the experience of a policy of initial interventional radiological treatment using transjugular intrahepatic portosystemic shunt

BACKGROUND AND AIMS: The optimal management of acute Budd-Chiari syndrome (BCS) with liver failure is controversial. Options include anticoagulation, portal systemic shunting or liver transplantation. In recent years, transjugular intrahepatic portosystemic shunts (TIPS) have been tried in place of shunt surgery. We report our experience with a policy of initial interventional radiological treatment (TIPS) in this patient group. METHODS: A consecutive, non-selected series of five patients with acute BCS with liver failure presenting to our liver unit over a 36-month period from October 2000 were treated with a policy of initial attempt at transjugular shunt. RESULTS: Stents were successfully inserted in four patients. In one patient the hepatic vein remnant could not be cannulated. One of the four stented patients had a hepatic venous web. Rapid recurrent portal and hepatic vein thrombosis occurred in one patient despite anticoagulation and trans-shunt thrombectomy. This patient and the patient with failed stenting underwent successful liver transplantation. One successfully stented patient died unexpectedly at home 2 weeks after TIPS insertion. Four of five patients are alive (80%) at a mean follow-up time of 30 months. CONCLUSION: Initial TIPS, with liver transplantation for treatment failures, may be a reasonable, cost-effective and surgery-sparing treatment for acute Budd-Chiari presenting with liver failure.     

Morphologic features of the normal and abnormal mitral valve

Anatomic and functional features of the normal and abnormal mitral valve are reviewed. Of 1,010 personally studied necropsy patients with severe (functional class III or IV, New York Heart Association) cardiac dysfunction from primary valvular heart disease, 434 (43%) had mitral stenosis (MS) with or without mitral regurgitation (MR): unassociated with aortic valve stenosis or regurgitation or with tricuspid valve stenosis in 189 (44%) patients, and associated with aortic stenosis in 152 (35%), with pure (no element of stenosis) aortic regurgitation in 65 (15%) patients, and with tricuspid valve stenosis with or without aortic valve stenosis in 28 (6%) patients. The origin of MS was rheumatic in all 434 patients. Of the 1,010 necropsy patients, 165 (16%) had pure MR (papillary muscle dysfunction excluded): unassociated with aortic valve stenosis or regurgitation or with tricuspid valve stenosis in 97 (59%) patients, and associated with pure aortic regurgitation in 45 (27%) and with aortic valve stenosis in 23 (14%) patients. When associated with dysfunction of the aortic valve, pure MR was usually rheumatic in origin, but when unassociated with aortic valve dysfunction it was usually nonrheumatic in origin. Review of operatively excised mitral valves in patients with pure MR unassociated with aortic valve dysfunction disclosed mitral valve prolapse (most likely an inherent congenital defect) as the most common cause of MR. Excluding the patients with MR from coronary heart disease (papillary muscle dysfunction), mitral prolapse was the cause of MR in 60 (88%) of the other 68 patients, and a rheumatic origin was responsible in only 3 of the 68 patients, all 68 of whom were greater than 30 years of age. Mitral anular calcification in persons aged greater than 65 years is usually associated with calcific deposits in the aortic valve cusps and in the coronary arteries. Because calcium in each of these 3 sites is common in older individuals residing in the Western World, it is most reasonable to view mitral anular calcification in older individuals as a manifestation of atherosclerosis. Mitral anular calcium appears to be extremely uncommon in persons with total serum cholesterol levels less than 150 mg/dl. Mitral anular calcium may produce mild MR and, if the deposits are heavy enough, MS.     

Enhancement of recovery of myocardial function by oxygen free-radical scavengers after reversible regional ischemia

Reperfusion after reversible regional ischemia has been shown to result in delayed recovery of myocardial function, but the mechanism responsible for this phenomenon remains unknown. We explored the potential role of oxygen-free radicals as mediators of postischemic dysfunction in open-chest dogs undergoing a 15 min occlusion of the left anterior descending coronary artery (LAD) followed by 2 hr of reperfusion. Treated animals (n = 19) received an infusion of the oxygen free-radical scavengers superoxide dismutase (SOD; 15,000 U/kg) and catalase (CAT; 55,000 U/kg) for 1 hr starting 15 min before LAD occlusion, while control animals (n = 20) received an equal volume of saline. SOD and CAT produced no discernible effect on heart rate, aortic pressure, or left atrial pressure. Collateral flow to the ischemic zone (radioactive microspheres) was 0.07 +/- 0.01 ml/min/g in both groups. The size of the occluded bed as determined by postmortem perfusion was 26.1 +/- 1.2% of the left ventricle in the control group and 26.5 +/- 0.9% in the treated group. Systolic wall thickening (an index of regional function) was assessed with an epicardial pulsed-Doppler probe. The two groups exhibited comparable systolic thickening under baseline conditions and similar degrees of dyskinesia during ischemia. Nevertheless, recovery of function (expressed as percent of baseline) was considerably greater in the treated dogs, both at 1 hr (43.8 +/- 14.3 vs 12.8 +/- 11.6) and 2 hr of reperfusion (74.2 +/- 8.4 vs 31.6 +/- 9.8, p less than .005). This improved recovery of function obtained with SOD and CAT suggests that oxygen-free radicals play an important role in the genesis of myocardial dysfunction after a brief episode of regional ischemia.     

The floating heart or the heart too fat to sink: Analysis of 55 necropsy patients

Certain clinical and morphologic findings are described in 55 patients whose hearts at necropsy contained so much fat that they floated in water. The patients were 47 to 89 years old (mean 67). Symptomatic coronary heart disease was present in 28 (51%) and valvular heart disease (mitral stenosis) in 3 (5%). The heart at necropsy was enlarged (>350 g for women and >400 g for men) in 45 patients (82%). The mean heart weight for the 31 women was 470 g and for the 24 men, 515 g. In addition to the severe increase in fat in the atrioventricular sulci and over both ventricles, the amount of fat in the atrial septum was increased in all patients. In 14 patients (25%), the thickness of the atrial septum cephaled to the fossa ovale was ≥2 cm. Excessive fat in this location is called “lipomatous hypertrophy of the atrial septum.” Of the 16 patients (29%) with fatal acute myocardial infarction, 7 (44%) had rupture of either the left ventricular free wall or ventricular septum. The high frequency of cardiac rupture in these patients supports the contention that rupture during acute myocardial infarction is more common in the fatty than in the non-fatty heart.     

Left-sided valvular active infective endocarditis. A study of forty-five necropsy patients

Clinical and anatomic features are described in forty-five necropsy patients with left-sided valvular active infective endocarditis. Vegetations in 53 per cent of the patients involved previously anatomically normal valves, and 76 per cent of all patients had previously functionally normal valves. Predisposing factors allowing entrance of virulent or unusual organisms or alterations of host defense mechanisms appear to account for the frequency of infective endocarditis on normal valves. Valvular dysfunction resulting from infective endocarditis occurred in at least 59 per cent and possibly as high as 74 per cent of the forty-five patients causing congestive heart failure in all. Myocardial lesions were present in 87 per cent of the thirty-eight patients in whom multiple histologic sections were examined, but in none did heart failure appear to result from these lesions. Papillary muscle necrosis was present in 58 per cent, but in none did it appear to cause mitral regurgitation. Congestive heart failure could not be attributed in any patient to myocardial lesions. Pericarditis occurred in eight patients (20 per cent), and in each a site of direct extension of the inflammation into the pericardium was apparent. Ring abscesses occurred in twelve of thirty-one patients with aortic valve vegetations and in none of twenty-six with mitral valve vegetations. Ring abscesses indicate severe destruction of valvular cusps and severe valvular dysfunction.