Environmental risk factors for infection with Mycobacterium avium complex

Infection with Mycobacterium avium complex is acquired from the environment, but risk factors for M. avium complex infection and disease are poorly understood. To identify risk factors for infection, the authors performed a 1998-2000 cross-sectional study in western Palm Beach County, Florida, using a population-based random household survey. M. avium complex infection was identified by use of the M. avium sensitin skin test. Of 447 participants, 147 (32.9%) had a positive test reaction, 186 (41.6%) had a negative test reaction, and, for 114 (25.5%), test results were indeterminate. Among the 333 participants with positive or negative M. avium sensitin skin tests, age-adjusted independent predictors of M. avium complex infection in a multivariate model included Black race (odds ratio = 3.8, 95% confidence interval: 2.2, 6.6), birth outside the United States (odds ratio = 2.1, 95% confidence interval: 1.1, 3.9), and more than 6 years' cumulative occupational exposure to soil (odds ratio = 2.7, 95% confidence interval: 1.3, 6.0). Exposure to water, food, or pets was not associated with infection. Results indicate that soil is a reservoir for M. avium complex associated with human infection and that persons whose occupations involve prolonged soil exposure are at increased risk of M. avium complex infection.

Antifungal susceptibilities of Cryptococcus neoformans cerebrospinal fluid isolates and clinical outcomes of cryptococcal meningitis in HIV-infected patients with/without fluconazole prophylaxis

OBJECTIVES

To compare the MICs of FLUconazole (FLU) and amphotericin B against isolates of Cryptococcus neoformans (C. neoformans) obtained from the CerebroSpinal Fluid (CSF); and clinical outcomes of HIV-infected patients diagnosed with cryptococcal meningitis.

MATERIAL AND METHOD

There were two groups including those who did not receive FLU (group A) and those who did receive either FLU 400 mg/week for primary prophylaxis cryptococosis or 200 mg/day for secondary prophylaxis cryptococosis (group B). CSF isolates of C. neoformans from group A and group B between January 2003 and October 2004 were retrospectively studied. The MICs were determined by using the standard NCCLS broth microdilution methods (M27-A). The MICs of FLU and amphotericin B, and clinical outcomes after 10 weeks of cryptococcal meningitis treatment were determined.

RESULTS

There were 98 isolates; 80 in group A and 18 in group B. The patients in group B had a higher proportion of previous opportunistic infections (p = 0.008). The other baseline characteristics between the two groups were not different. The median (range) MIC of FLU was 8.0 (0.5-32) microg/ml in group A, and 6.0 (0.5-32) microg/ml in group B (p = 0.926). The median (range) MIC of amphotericin B was 0.25 (0.03-1.0) microg/ml in group A, and 0.25 (0.12-1.0) microg/ml in group B (p = 0.384). Sixty patients from group A and 14 from group B received standard treatment and continued to follow-up. After the 10-week treatment, 39/60 (65%) patients in group A and 7/14 (50%) in group B had complete recovery (p = 0.364; RR = 0.538, 95%CI = 0.166-1.742). The overall mortality rate was 14/60 (23.3%) in group A and 7/14 (50.0%) in group B (p = 0.096; RR = 3.286, 95%CI = 0.983-10.979).

CONCLUSION

The MICs of FLU and amphotericin B against CSF isolates of C. neoformans and clinical outcomes between HIV-infected patients who receive or did not receive FLU prophylaxis are not different.

Tuberculosis and the eye

OBJECTIVES

1. To refresh knowledge on the epidemiology, pathogenesis, clinical features, investigations and treatment of ocular tuberculosis; 2. To highlight the ocular complication of tuberculosis.

METHOD

Through an internet search and review of current literature on tuberculosis and its ocular complications, the information relevant to the objectives was obtained.

CONCLUSIONS

TB can affect any structure in the eye and adnexae. Ocular TB is not easy to diagnose because most times there is no concurrent active systemic tuberculosis. However, once TB is confirmed, treatment is generally the same as for systemic TB. Topical steroids are given in addition, in cases like phlyctenulosis. Early diagnosis and treatment of ocular TB can prevent blindness or severe ocular morbidity. With the growing epidemic of HIV and the consequent increased risk of developing TB, ophthalmologist and eye care workers are, therefore, advised to heighten their suspicion of ocular TB.

Fungal arthritis and osteomyelitis

Fungal arthritis and osteomyelitis are uncommon diseases and generally present in an indolent fashion. The incidence of fungal bone and joint dis-ease is increasing with an increase in the prevalence of factors predisposing to invasive fungal disease, such as the use of central venous catheters, broad spectrum antibiotics, immunosuppression, and abdominal surgery. Definitive diagnosis relies on bone or synovial culture or biopsy. Successful management has traditionally consisted of amphotericin B in combination with surgical debridement. Given the rarity of this disease, treatment is not well defined, but reports of success with the use of azole antifungal agents, including itraconazole, fluconazole, voriconazole, and posaconazole, are promising.

Suppurative tenosynovitis and septic bursitis

Suppurative tenosynovitis and septic bursitis are closed space infections of the musculoskeletal system. Appropriate antibiotics in combination with incision and drainage are generally recommended. Aggressive surgical management is particularly important in tenosynovitis to prevent tendon necrosis. Empiric antibiotic coverage should be directed toward staphylococci and streptococci. Patient characteristics and epidemiologic exposures may provide clues to unusual causative organisms that are occasionally encountered, such as Neisseria gonorrhoeae, Pasteurella multocida, atypical mycobacteria, fungi, and protothecosis.

Tropical and Temperate Pyomyositis

Pyomyositis is a primary infection of skeletal muscle not arising from contiguous infection, presumably hematogenous in origin, and often, but not invariably, associated with abscess formation. Classically, pyomyositis is an infection of the tropics, occurring in previously active and healthy young men. Pyomyositis in temperate countries is often regarded as an infection that occurs in hosts who are immunocompromised or otherwise debilitated. However,this distinction may be somewhat artificial, as tropical pyomyositis may be partly related to underlying infection with HIV or parasites, and temperate pyomyositis has been reported in healthy and athletic persons. This article discusses the pathogenesis, clinical presentation, diagnosis, and management of pyomyositis in the tropical and temperate settings.

Short report: asymptomatic Cryptosporidium hominis infection among human immunodeficiency virus-infected patients in Tanzania

Few data exist on the relative importance of individual Cryptosporidium species in acquired immunodeficiency syndrome cryptosporidiosis. We characterized 127 inpatients infected with human immunodeficiency virus (HIV) in Tanzania for their CD4 cell count and by stool analysis, including Cryptosporidium immunofluorescence and polymerase chain reaction-restriction fragment length polymorphism. Cryptosporidium was detected in patients both with and without diarrheal symptoms (defined as > or = 3 liquid stools/day, 11 of 61 versus 11 of 66; P = not significant) and was a marker for low CD4 cell count (median = 124/microL versus 212/microL in Cryptosporidium-negative patients; P < 0.04). Cryptosporidium hominis was the predominant species in this region and was associated with a longer duration of symptoms, a higher rate of asymptomatic infection, and a lower CD4 cell count versus C. parvum-infected patients (P < 0.05). This study suggests there may be important differences in the natural history of Cryptosporidium infection in HIV-infected persons depending on parasite species.

Recent advances in acquired immunodeficiency syndrome (AIDS)-related lymphoma

Human immunodeficiency virus-infected patients are at an increased risk for developing both Hodgkin and non-Hodgkin lymphoma when compared with the general population. With the remarkable decrease in the incidence of opportunistic infections since the availability of highly active antiretroviral therapy (HAART), acquired immune deficiency syndrome-related lymphoma (ARL) is now the second most common cancer associated with human immunodeficiency virus after Kaposi sarcoma. Over the last few years, advances in our understanding of the molecular biology of this heterogeneous group of lymphomas have led to the adoption of new classification systems. The prognosis of patients with ARL has improved dramatically with the availability of HAART, and the survival of many of these patients is now comparable to patients in the general population. Apart from the contribution of HAART, this improvement in prognosis can also be attributed to new initiatives in treatment of these patients, such as the use of effective infusional regimens, the feasibility of high-dose therapy with peripheral stem cell rescue for relapsed or refractory disease, and better supportive care. Nonetheless, several controversial issues persist, including the optimal timing of HAART with combination chemotherapy, the role of rituximab when incorporated into treatment regimens, and the optimal therapy for patients with acquired immunodeficiency syndrome-related Burkitt lymphoma. This article reviews the changes in the epidemiology of ARL in the era of HAART, advances in the biology of ARL, new developments in the management of patients with ARL, and several of the controversial issues that oncologists may encounter in the care of these patients.

Epstein-Barr virus associated with primary CNS lymphoma and disseminated BCG infection in a child with AIDS

BACKGROUND

AIDS patients are at increased risk of developing concurrent infections with viral, parasitic, fungal or mycobacterial organisms. They can present constitutional symptoms of fever and weight loss, either due to infections or an underlying lymphoma which may coexist.

CASE REPORT

A child with HIV-AIDS and mild encephalopathy is reported, who during the course of a confirmed disseminated mycobacterial disease developed neurological impairment. Post-mortem examination revealed disseminated BCG infection and Epstein-Barr associated primary CNS lymphoma. Epstein-Barr virus (EBV) presence was assessed by LMP-1 protein labelling by immunohistochemistry and in situ hybridisation (ISH) for Epstein-Barr virus-encoded RNAs (EBERs) in formalin-fixed and paraffin-embedded sections.

CONCLUSIONS

BCG vaccination among HIV-1 infected children leads to the risk of disseminated BCG infection. BCG immunization programmes should be reconsidered for children at risk of HIV infection, because the risk of delayed complications is independent of the immunological status at the time of the vaccination. Only isolated cases of primary CNS lymphoma occurring in HIV-infected children have been reported, and a striking association with EBV infection has been demonstrated.

[Ocular manifestations in patients with human immunodeficiency virus infection before and after the introduction of highly active antiretroviral therapy]

The aim of this study was to determine and compare the incidence of various ophthalmlogic changes before anfd after the initiation of highly active antiretroviral therapy (HAART) in HIV-infected patients treated at the University Hospital for Infectious Diseases "Dr. Fran Mihaljević" in Zagreb. This retrospective longitudinal analysis included all adult patients with confirmed HIV-1 infection divided into two groups: period before HAART (1995-1997) and period after HAART (1998-2000). Only those patients who underwent at least two ophthalmologic examinations in any of the two or in both periods were considered eligible. In total, 85 patients were enrolled in the study, 50 during the 1995-1997 period and 47 in the period 1998-2000 (12 patients were monitored in both periods). The mortality rate was significantly lower in patients treated during the HAART era, with an average decrease in mortality rates of 59.3%. During the period of ophthalmologic monitoing from 1995 to 1997, only 9 (18%) patients received HAART, and 33 (70.2%) in the period 1998-2000. In total, 208 ophthalmic abnormalities were recorded, 132 (63.5%) in the first and 76 (36.5%) in the second period. Vascular changes were most frequently diagnosed (113/208 or 54.3% cases) of which cotton-wool exudates in 55 and microaneurysms in 54 cases. Cytomegalovirus (CMV) retinitis was most commonly diagnosed among infectious ocular complications (altogether 39 episodes). Changes in the anterior segment were observed in only 11/208 (5.3%) cases, while neuro-ophthalmic manifestations were sees in 39/208 patients (18.7%). The incidence of CMV-retinitis episodes in the first monitored period was 57.2 (95% CI, 38.5-86.6) per 100 years of follow-up and in the HAART era 7.6 (95% CI, 1.6-22.4; p<0.0001) per 100 years of follow-up. The visual acuity in patients from the HAART era was significantly more frequently preserved than in patients from the pre HAART era on follow-up examinations (p<0.001). Our study showed that the incidence of CMV-retinitis declined significantly in the period 1998-2000, while the decrease in the incidence rates of other ocular manifestations was less profound. In contrast to the pre HAART era, there was no worsening of visual acuity in the HAART era.

Cytokine responses induced by Mycobacterium tuberculosis in patients with HIV-1 infection and tuberculosis

OBJECTIVE

Tuberculosis (TB) is an important opportunistic infection in HIV patients. Immune responses to Mycobacterium tuberculosis in HIV/TB patients were evaluated.

METHODS

Fifteen patients with HIV/TB, ten with HIV, four with TB, and five controls were enrolled. Peripheral blood mononuclear cells were isolated and stimulated with mycobacterial antigen (PPD). Interferon (IFN)-gamma and TNF-alpha in culture supernatants were measured by ELISA.

RESULTS

IFN-gamma and TNF-alpha production after PPD stimulation was markedly decreased in HIV patients, but not in HIV/TB patients. In HIV patients with a CD4 cell count of less than 200/mm3, IFN-gamma and TNF-alpha production after PPD stimulation was higher in HIV/TB patients than in HIV patients. Cytokine responses to M. tuberculosis reconstituted after highly active antiretroviral therapy (HAART) and were prominent in HIV/TB patients.

CONCLUSIONS

Cytokine responses to M. tuberculosis were retained in HIV-infected patients with tuberculosis, even in patients with a CD4 cell count of less than 200/mm3, and reconstituted after HAART.

Natural history of hepatitis C virus infection: from chronic hepatitis to cirrhosis, to hepatocellular carcinoma

Hepatitis C is a heterogeneous disease and is responsible for considerable mortality and morbidity. The hepatitis C virus (HCV) infects nearly 170 million people world-wide. More than 80% of infected individuals develop chronic infection; the remaining 10-20% develop spontaneous clearance with natural immunity. Acute hepatitis is icteric in only 20% of patients and is rarely severe. The majority of patients who develop chronic HCV infection are asymptomatic; but 60-80% develop chronic hepatitis as indicated by elevated alanine aminotransferase (ALT), around 30% maintain persistently normal ALT levels despite having detectable HCV-RNA in serum. One-third of chronically infected patients develop progressive liver injury, fibrosis and cirrhosis over a period of 20-30 years. The relationship between virus load, HCV genotype, quasi-species variability and progression of liver disease is controversial. Acquired infection after age 40, male sex, excessive alcohol-consumption, hepatitis B virus (HBV) or HIV co-infection, steatosis, and immunosuppressed state have been identified as co-factors associated with progression of fibrosis and development of cirrhosis. In patients with cirrhosis, the incidence of hepatocellular carcinoma is 2-5% per year. At present, HCV-related end-stage cirrhosis is the first cause of liver transplantation.

Profile of Patients With Kaposi's Sarcoma in the Era of Highly Active Antiretroviral Therapy

Purpose

Since the advent of highly active antiretroviral therapy (HAART), the incidence of Kaposi's sarcoma (KS) among AIDS patients has declined both nationwide and in King County, Washington. We sought to compare clinical parameters of patients diagnosed with KS in the pre-HAART (1990 to 1996) and HAART (1997 to 2002) eras.

Methods

We used patient data abstracted from the Adult/Adolescent Spectrum of HIV-Related Diseases study of Public Health—Seattle and King County.

Results

Patients diagnosed with KS in the HAART era (n = 40) were significantly more likely (P < .05) than pre–HAART-era KS patients (n = 366) to be diagnosed with alcohol problems (43% v 18%), noninjection drug use (45% v 18%), injection drug use (25% v 10%), psychosis (25% v 13%), and hypertension (13% v 2%). Although median CD4+ count and HIV-1 viral load at the time of KS diagnosis were not significantly different between the two groups, significantly fewer (P < .01) HAART-era KS patients developed opportunistic illnesses (OIs) during their follow-up. The risk of dying among KS patients diagnosed in the HAART era is significantly lower (P < .01) than for KS patients diagnosed in the pre-HAART era (hazard ratio, 0.24).

Conclusion

Although HAART-era KS patients in King County were as likely to have a depleted CD4+ cell count and high HIV-1 viral loads at the time of KS diagnosis as pre-HAART KS patients, they survived longer and fewer of them were diagnosed with other OIs. They also had an increased prevalence of substance abuse and mental illness, contributing to a dynamic and changing KS clinical profile.

Management of sexually transmitted infections in HIV positive individuals

PURPOSE OF REVIEW

This review aims to summarize recent developments in the epidemiology and management of sexually transmitted infections in HIV positive individuals. It will also discuss briefly the legal aspects of disclosure in relation to HIV transmission.

RECENT FINDINGS

There has been a dramatic increase in the reported number of cases of syphilis globally in recent years. In the United Kingdom this has mainly been observed among HIV positive men who have sex with men (MSM). Since 2003 there have been a series of outbreaks of lymphogranuloma venereum reported in several European cities occurring mostly in HIV positive MSM. Sexual transmission of hepatitis C is increasing and appears to be more common in HIV positive MSM. Legal issues regarding HIV transmission have also come to the fore, becoming an important part of the discussion of sexual health with an HIV positive patient.

SUMMARY

Increases in sexually transmitted infection among HIV positive individuals suggest a worrying lack of adherence to safe sex guidelines and needs to be addressed urgently. The transmission of HIV is facilitated by the presence of certain sexually transmitted infections. Management of sexual health is an essential part of HIV care.

Cytologic diagnosis of pancreatic tuberculosis in immunocompetent and immunocompromised patients: a report of 2 cases

BACKGROUND

Pancreatic tuberculosis (PT) is a very rare occurrence in the setting of extrapulmonary tuberculosis. It usually occurs as a complication of miliary tuberculosis in immunodeficient individuals, particularly with HIV infections, but isolated involvement in an immunocompetent patient is extremely rare. Pancreatic involvement by tuberculosis in immunocompromised states, such as AIDS, and isolated involvement in immunocompetent patients require a high index of suspicion. Fine needle aspiration cytology under imaging guidance is highly conclusive.

CASES

A patient presented with diabetes mellitus and a pancreatic mass clinically diagnosed as pancreatic carcinoma. A second patient, who was HIV seropositive, presented with generalized lymphadenopathy and a pancreatic mass, clinically diagnosed as lymphoma. These were conclusively diagnosed by fine needle aspiration cytology (FNAC) as PT under imaging guidance. After antituberculous therapy the first patient showed a dramatic improvement, whereas the second died; an autopsy was performed. Because of the atypical presentation of PT in immunocompromised and immunocompetent patients, FNAC can be used as a first-line diagnostic intervention. FNAC under imaging guidance is sensitive, specific, rapid and inexpensive. It resolves the diagnostic dilemma and thus avoids major surgery for a clinically diagnosed neoplasm.

Modifications of haematological series in patients co-infected with human immunodeficiency virus and hepatitis C virus during treatment with interferon and ribavirin: differences between pegylated and standard interferon

Therapy with interferon and ribavirin for hepatitis C virus (HCV) infection induces a decrease in several haematological population counts. It is unclear whether haematological toxicity is more severe in patients co-infected with HCV and human immunodeficiency virus (HIV). This study analysed the evolution of haematological population counts during and after interferon and ribavirin therapy for chronic HCV infection. Eleven patients co-infected with HIV and HCV and treated with pegylated interferon plus ribavirin, and ten treated with standard interferon plus ribavirin, were analysed. With reference to baseline values, neutrophil counts decreased by an average of 45% (range 18-67%), total lymphocytes by 50% (16-63%), CD4 lymphocytes by 54% (16-61%), haemoglobin by 9% (5-16%) and platelets by 31% (16-45%). The nadir of the decrease was reached in the first weeks of therapy and was maintained while patients were receiving treatment. The reduction in all series was higher with pegylated interferon. Patients recovered their baseline counts after finishing the treatment. No cases of haemorrhage or outstanding infection were detected during follow-up.

[Molecular pathogenesis in tuberculosis complicated with AIDS]

HIV-1 infection is a major cause of worldwide epidemic of tuberculosis. There is increasing clinical evidence that coinfection with M. tuberculosis accelerates progression of AIDS. We found that, in vivo, HIV-1 load and mutation increase in involved lung segments in patients with pulmonary tuberculosis. We also reported that Mycobacterium tuberculosis stimulates HIV-1 replication by enhancing transcription on the 5' LTR in a macrophage cell line, THP-1, in vitro. In contrast, HIV-1 replication is suppressed by M. tuberculosis infection of monocytes derived macrophages (MDM) or differentiated monocytic THP-1 cells. We observed that HIV-1 5' LTR function was repressed in PMA differentiated THP-1 cells after co-infection with M. tuberculosis. Point mutations in C/EBP beta binding domains of the HIV-1 LTR negative regulatory element (NRE) abolished promoter repression. Monocyte-derived macrophages and differentiated THP-1 cells increased expression of the 16kDa inhibitory form of C/EBP after M. tuberculosis co-infection. Bronchoalveolar lavage cells obtained from normal controls and alveolar macrophages from uninflamed lung of tuberculosis patients also expressed the 16kDa inhibitory form of C/EBP. However, alveolar macrophages from lung segments involved with pulmonary tuberculosis had markedly reduced C/EBP expression. These data suggest that 16kDa isoform of C/EBP plays an important role for the control of HIV-1 replication in macrophages. We propose derepression of HIV-1 LTR mediated transcription as one mechanism for enhanced HIV-1 replication observed in pulmonary tuberculosis. Since the cellular immune response in pulmonary tuberculosis requires lymphocyte/macrophage interaction, a model system was developed in which lymphocytes were added to AM. Contact between lymphocytes and AM reduced inhibitory C/EBP beta, activated NF-kappaB and enhanced HIV-1 replication. If contact between lymphocytes and macrophages was prevented, inhibitory C/EBP beta expression was maintained and the HIV-1 long terminal repeat (LTR) was not maximally stimulated although NF-kappaB was activated. Antibodies which cross-linked macrophage expressed B-7, VCAM and CD-40 were used mimic lymphocyte contact. Cross-linking antibodies abolished inhibitory C/EBP beta expression; however, the HIV-1 LTR was not maximally stimulated and NF-kappaB was not activated. Maximal HIV-1 LTR stimulation required both lymphocyte derived soluble factors and cross-linking of macrophage expressed co-stimulatory molecules. These results demonstrate that neither contact nor soluble factor(s) are sufficient to maximally enhance HIV-1 LTR activity in macrophages. Contact between activated lymphocytes and macrophages is necessary to downregulate inhibitory C/EBP beta, thereby derepressing the HIV-1 LTR. Lymphocyte derived soluble factor(s) activate NF-kappaB, further enhancing the HIV-1 LTR.