Human immunodeficiency virus infection and the thyroid.

Abnormalities of thyroid function are associated with a number of systemic conditions, including patients infected with human immunodeficiency virus (HIV). Most patients with early HIV infection and a stable body weight have normal thyroid function. Subtle abnormalities of a number of thyroid function tests have been reported during the early asymptomatic phase of HIV disease. These include an inappropriately normal triiodothyronine (T(3)) and reduced reverse triiodothyronine (rT(3)), and increased thyroxine-binding globulin (TBG) levels. Opportunistic infections involving the thyroid gland, neoplasms such as lymphoma and Kaposi's sarcoma, and medications can alter the thyroid function in individuals with more advanced HIV infection. If thyroid dysfunction is diagnosed in an HIV-infected patient, it should be treated in the usual manner. However, high index of suspicion and caution in the interpretation of thyroid function tests in patients with HIV disease are needed for optimal diagnosis and treatment.     

Human immunodeficiency virus infection, anemia, and survival.

Anemia, a common hematologic complication in human immunodeficiency virus (HIV)-infected patients, can be caused by mechanisms including infections, neoplasms, or drug treatment. Studies have consistently found anemia to be associated with reduced survival, even when potentially confounding factors were controlled for. Importantly, recovery from anemia has been shown to reduce this risk to approximately the same level as seen among patients never having had anemia. Although anemia traditionally has been treated with blood transfusions, recent studies have shown recombinant human erythropoietin (r-HuEPO) to be effective in elevating hematocrit values and reducing transfusion requirements in HIV-infected patients who have endogenous erythropoietin levels of < or = 500 IU/L. Therapy with r-HuEPO has been shown to be safe and well tolerated. In a recent study, moreover, receipt of erythropoietin was associated with a decreased risk of death, whereas transfusion was associated with an increased risk. If these results are confirmed, the link between r-HuEPO and decreased risk of death in HIV-infected patients with anemia will be further strengthened.     

Human immunodeficiency virus, smoking and self-rated health in Harare, Zimbabwe.

SETTING: Twenty-two urban factories in Harare. OBJECTIVE: To determine the relationship between the human immunodeficiency virus (HIV), smoking and self-rated health in a high HIV prevalence urban workforce. DESIGN: Cross-sectional survey. RESULTS: Of 7482 employees, 6111 (82%) consented to interview and anonymous HIV serology; 88% were male; median age was 34 years. HIV prevalence was 19%. Current (median 6 cigarettes per day) and former smoking were reported by 17% and 7%, respectively. Smoking (current or former) was more common among HIV-positive (27%) than -negative participants (17%; P < 0.001). Factors significantly associated with being a smoker on multivariate analysis were being HIV-infected (OR 1.5, 95% CI 1.4-1.7), older age (P < 0.001), non-Christian (OR 1.6, 95% CI 1.2-2.2) and manual job (OR 1.4, 95% CI 1.2-1.6). Women (OR 0.05, 95% CI 0.03-0.11) and the better educated (OR 0.7, 95% CI 0.5-0.9) were significantly less likely to smoke. HIV-positive smokers had the highest risk of reporting poor health (adjusted OR compared to HIV-negative non-smokers 3.4, 95% CI 2.3-5.0). CONCLUSIONS: Smoking was significantly more common among HIV-positive than -negative employees in this predominantly male workforce. There was evidence of a combined effect on self-rated poor health, a variable shown to be a strong independent predictor of mortality in industrialised countries. Interventions to encourage smoking cessation may be an important component of HIV care in Southern Africa.     

Human immunodeficiency virus infection and the liver

Liver disease in human immunodeficiency virus(HIV)-infected individuals encompasses the spectrum from abnormal liver function tests,liver decompensation,with and without evidence of cirrhosis on biopsy,to non-alcoholic liver disease and its more severe form,non-alcoholic steatohepatitis and hepatocellular cancer.HIV can infect multiple cells in the liver,leading to enhanced intrahepatic apoptosis,activation and fibrosis.HIV can also alter gastro-intestinal tract permeability,leading to increased levels of circulating lipopolysaccharide that may have an impact on liver function.This review focuses on recent changes in the epidemiology,pathogenesis and clinical presentation of liver disease in HIV-infected patients,in the absence of co-infection with hepatitis B virus or hepatitis C virus,with a specific focus on issues relevant to low and middle income countries.     

Human immunodeficiency virus infection and the intestine

HIV is a retrovirus infecting CD4-positive cells causing profound immunosuppression, eventually clinically manifest as AIDS. The cells principally infected by HIV are T4 lymphocytes (helper) and macrophages. The eventual loss of helper cell function is the prime reason for immunodeficiency which renders the individual susceptible to opportunistic infections. HIV infection was first described in male homosexuals. However, the trend now is for seroprevalence to rise rapidly in intravenous drug abusers in the West. In addition, African AIDS is thought to be almost exclusively heterosexual in nature, a paradox which is not yet fully explained in comparison with the relatively low but increasing incidence in heterosexuals in the Western world. Virtually every organ system in the body can be affected clinically during the course of HIV infection. The gastrointestinal tract is a major target, and the physiological sequelae are an important cause of morbidity and mortality. The pathophysiology of intestinal infection is not yet fully understood, however two main mechanisms have been postulated. The first is reduced intestinal immunity resulting in chronic opportunistic infections, which themselves caused altered intestinal function. The second is that HIV itself affects the intestinal mucosa, causing malfunction. The mechanisms by which the latter occurs are controversial but may result from either direct infection of mucosal epithelial cells or macrophages within the mucosa. Reports have documented the presence of HIV genome in both epithelial argentachromaffin cells and macrophages. In addition, profound degeneration of intrinsic jejunal autonomic neurones has been demonstrated, but the functional significance of such denervation is as yet unknown. The clinical stage of HIV infection at which intestinal mucosal immunity fails is by definition when opportunistic infection occurs (that is, clinical progression to stage IV disease), namely AIDS, however a detailed knowledge of the mechanisms of intestinal immune failure are lacking.     

Human immunodeficiency virus and respiratory infection

Pulmonary disease remains a major problem for the 33 million individuals who are thought to be infected with human immunodeficiency virus (HIV) worldwide. Respiratory infections are responsible for a large number of the 2 million deaths that occur each year in association with HIV disease. In countries where the majority of the population can access highly active antiretroviral therapy, morbidity and mortality rates have been cut by up to 80%. This has allowed the withdrawal of specific opportunistic infection prophylaxis when immune restoration is deemed to be adequate. Recommendations have been published concerning Pneumocystis carinii prophylaxis. This year has also seen further reports of drug-resistant isolates of Pneumocystis carinii. The clinical relevance of this is still debated. Tuberculosis remains a global problem. The complexity of the interactions between specific anti-HIV and anti-tuberculous treatment have been highlighted. In the developing world, the importance of immunization and prophylaxis (against bacteria and mycobacteria) have recently been further defined in a number of studies.     

AIDS: immunologic abnormalities following human immunodeficiency virus infection

Following human immunodeficiency virus (HIV) infection, there is an ordered progression of immunologic abnormalities that results from the selective infection of the T4 helper/inducer subset of T lymphocytes. The loss of helper T-cell function disrupts both the cellular and humoral aspects of the immune response. The T lymphocytes decrease in both number and function. The peripheral blood B lymphocytes demonstrate marked polyclonal activation and are unable to mount a serologic response to new antigens. The infected monocytes and macrophages serve as reservoirs for HIV and act as vehicles that transport the virus to target organs. Decreased activity of natural killer cells may promote progression of acquired immunodeficiency syndrome (AIDS). Factors that suppress the reaction of T and B lymphocytes to stimuli have been identified in the sera of AIDS patients. In conclusion, HIV infection causes progressive dysfunction and destruction of the entire immune system, resulting in severe opportunistic infections, neoplasms, and shortened survival of AIDS patients.     

Human immunodeficiency virus infection associated arthritis: clinical characteristics.

OBJECTIVE: To define the frequency and characteristics of human immunodeficiency virus (HIV) associated arthritis. METHODS: A total of 270 patients with HIV infection were prospectively evaluated for the presence of rheumatic complaints. Diagnosis of HIV infection was performed by ELISA and confirmed by Western blot, and all HIV patients were classified according to the US Centers for Disease Control criteria. RESULTS: Twenty-one (7.8%) patients presented with HIV associated arthritis. Other arthritides including HLA-B27 related, such as Reiter's syndrome, psoriatic arthritis, and rheumatoid arthritis, were excluded. Seventeen were men and 4 women, with a mean age of 34.8 years (SD 11.1). Fourteen (66%) were homosexuals, 4 (19%) intravenous drug users, and 3 (14%) heterosexuals. Twelve (57%) were in stage IV, 5 (23%) in stage III, and 4 (9%) in stage II. Ten (47%) patients had oligoarticular involvement, 8 (38%) monoarticular, 2 (9%) asymmetric polyarthritis, and one (4%) symmetric polyarthritis. Rheumatoid factor and HLA-B27 antigen were negative in all (15) patients studied. The mean duration of arthritis was 2 weeks (1-24). No differences in duration of arthritis were found among the different risk factors (p = 0.811), HIV stages (p = 0.205), and type of articular involvement (p = 0.252). There was, however, a trend between the number of involved joints and stages of HIV infection (p = 0.13). CONCLUSION: The pattern of joint involvement of HIV associated arthritis is similar to that of other viral disorders: acute onset, short duration, no recurrences, and no erosive changes.     

Human immunodeficiency virus infection and renal failure

Renal manifestations are an important component of HIV disease. Renal disease significantly contributes to morbidity and mortality in patients with HIV. Great progress has been made in identifying specific glomerular lesions and its pathogenesis. Newer antiretroviral agents offer great promise in preventing renal disease and also in patients with established HIVAN. Survival of patients with HIV and ESRD (irrespective of cause) who are receiving RRT continues to improve over the years. Acute reversible renal failure, a preventable complication, is also declining in hospitalized HIV patients. More and more physicians, who in the past were reluctant to care for patients with HIV and renal failure because of grim prognosis, are now becoming familiar with the renal sequelae and are encouraged by recent favorable results. As knowledge about viruses is expanding, the proper use of newer highly effective antiretroviral and other agents in complicated patients should further improve both the survival and quality of life in patients with HIV infection and renal disease.     

Human immunodeficiency virus infection in pregnancy

The incidence and prevalence of human immunodeficiency virus (HIV) infection in women of child-bearing age continue to increase both internationally and in Canada. The care of HIV-infected pregnant women is complex, and multiple issues must be addressed, including the current and future health of the woman, minimization of the risk of maternal-infant HIV transmission, and maintenance of the well-being of the fetus and neonate. Vertical transmission of HIV can occur in utero, intrapartum and postpartum, but current evidence suggests that the majority of transmission occurs toward end of term, or during labour and delivery. Several maternal and obstetrical factors influence transmission rates, which can be reduced by optimal medical and obstetrical care. Zidovudine therapy has been demonstrated to reduce maternal-infant transmission significantly, but several issues, including the short and long term safety of antiretrovirals and the optimal use of combination antiretroviral therapy in pregnancy, remain to be defined. It is essential that health care workers providing care to these women fully understand the natural history of HIV disease in pregnancy, the factors that affect vertical transmission and the management issues during pregnancy. Close collaboration among a multidisciplinary team of knowledgeable health professionals and, most importantly, the woman herself can improve both maternal and infant outcomes.     

Human immunodeficiency virus infection and acute deep vein thromboses.

Abnormalities that predispose to a hypercoagulable state with an increased incidence of venous thrombosis have been described in human immunodeficiency virus (HIV) infections and are associated with an increased mortality. A recent systematic review by Klein et al concluded that further studies are essential to elucidate the link between HIV infection and deep vein thrombosis (DVT). We prospectively evaluated 24 consecutive, active people presenting with an acute DVT; 13 consented to HIV testing, revealing an HIV prevalence of 84% (95% confidence interval [CI], 0.65-1.04). In a matched healthy control group, the HIV prevalence was 4% (95% CI, 0.039-0.041). The high HIV prevalence in the DVT group that consented to testing was also significantly higher compared to that in the South African population, estimated to be 10% in 2005. Although the study numbers were low, a statistically significant increased prevalence of HIV infection was found in patients with acute DVTs.     

Human immunodeficiency virus 1 infection, cocaine, and coronary calcification

BACKGROUND: Although cocaine use and human immunodeficiency virus (HIV) infection have been linked with clinical cardiovascular disease, the effects of cocaine use and HIV infection, especially the combination of the 2, on subclinical disease have rarely been reported. The objective of this study was to evaluate whether cocaine use alone, HIV infection alone, or a combination of the 2 is associated with coronary calcification, a marker of subclinical atherosclerosis. METHODS: Between May 20, 2000, and March 31, 2003, 224 black study participants from Baltimore were enrolled in an observational study of subclinical atherosclerosis as related to HIV and cocaine use. Interviews about sociodemographic characteristics and drug use behaviors, clinical examinations, echocardiographic examinations, lipid profiles, high-sensitivity C-reactive protein tests, and computed tomographic scans for coronary calcium were performed. Although the overall investigation is a cohort study, the data presented herein are cross sectional only. RESULTS: The highest proportion (37.6%) of presence of coronary calcification was in the HIV-positive and cocaine-positive group, followed by 29.8% in the HIV-negative and cocaine-positive group, 28.6% in the HIV-positive and cocaine-negative group, and 18.8% in the HIV-negative and cocaine-negative group. Univariate analysis showed that HIV, cocaine use, and both were associated with a higher number of lesions, calcified area, volume, and calcium score. In multiple regression analysis with adjustment for age, body mass index, low-density lipoprotein cholesterol level, triglyceride level, mean corpuscular volume, and systolic blood pressure, HIV, cocaine use, and both were independently associated with coronary calcification. CONCLUSION: These results suggest that HIV infection alone, cocaine use alone, or the 2 combined may contribute to early subclinical atherosclerotic cardiovascular disease.