AIDS-Related opportunistic illness and potent antiretroviral therapy

Exposure assessment of toxic metals and organochlorine pesticides among employees of a natural history museum

Chemical compounds such as arsenic, mercury and organochlorine pesticides have been extensively used as preventive and curative conservation treatments for cultural and biological collections to protect them from pest and mold infestations. Most of the aforementioned compounds have been classified as carcinogenic, mutagenic and teratogenic and represent a health risk for members of staff exposed to contaminated objects. The present study addresses the internal exposure of 28 museum employees in Museum für Naturkunde Berlin by measuring arsenic species and mercury in urine as well as hexachlorocyclohexane isomers (α-HCH, β-HCH, γ-HCH), hexachlorobenzene (HCB), dichlorodiphenyltrichloroethane (4,4'-DDT) and its main metabolite, dichlorodiphenyldichloroethylene (4,4'-DDE), and pentachlorophenol (PCP) in blood serum. This study was carried out in order to assess the internal exposure of Natural History Museum staff members to toxic metals and organochlorine pesticides. During a working week, two blood samples and five urine samples were taken from each participant, involving 8 women and 20 men. Information about work activity and exposure related factors such as dust development through work, use of personal protective equipment, as well as a nutrition diary were obtained through a questionnaire. Information on fish and seafood intakes as well as amalgam fillings was also available. The results of the study showed that the museum staff members had quantified concentrations of arsenic (median of 6.4 μg/l; maximum of 339 μg/l), mercury (median of 0.20 μg/l; max of 2.6 μg/l), β-HCH (median of 0.12 μg/l; max of 0.39 μg/l) and 4,4'-DDT (median of 0.050 μg/l; max of 0.82 μg/l). Despite that all the concentrations were below the established reference values, multivariate regression models were able to show that museum staff members are currently exposed to the aforementioned compounds while handling museum objects. To validate our findings, further studies are required.

Monitoring of arsenic, mercury and organic pesticides in particulate matter, ambient air and settled dust in natural history collections taking the example of the Museum für Naturkunde, Berlin

Chemical compounds such as arsenic, mercury and organochlorine pesticides have been extensively used as preventive and curative conservation treatments for cultural and biological collections to protect them from pest and mould infestations. Most of the aforementioned compounds have been classified as carcinogenic, mutagenic and teratogenic and represent a health risk for staff exposed to contaminated objects. A total of 30 compounds were analysed in settled dust, particulate matter and surrounding air collected at several locations in the natural history collections and adjacent rooms of the Museum für Naturkunde, Berlin (MfN, Natural History Museum, Berlin, Germany). Gas chromatography and mass spectrometry techniques were used to quantify dichlorodiphenyltrichloroethane (2,4'-DDT; 4,4'-DDT) and their metabolites (2,4'-DDE; 4,4'-DDE; 2,4'-DDD; 4,4'-DDD), hexachlorobenzene (HCB), 3 isomers of hexachlorocyclohexanes (α-HCH, β-HCH, γ-HCH), the degradation product of γ-HCH with similar toxicological profile, gamma-pentachlorocyclohexene (γ-PCH) and pentachlorophenol (PCP). Atomic absorption spectrometry was used to analyse arsenic and mercury. In order to assess the pathways of contamination with biocides in dust, formations of particulate matter during individual daily work activities, particle number concentrations (PNCs) were measured. Heavy element concentrations found at the MfN were higher than the organochlorine compounds. The maximum concentration of arsenic and mercury in dust was 3507 mg/kg and 32 mg/kg, respectively, and in air, 48 ng/m³ and 1.6 ng/m³, respectively. The maximum concentration of the sum of DDTs in dust was 2 mg/kg (not detected in air); for PCP, the maximum levels in dust and air were 0.65 mg/kg and 10 ng/m³, respectively; for γ-HCH, 130 mg/kg and 320 ng/m³, respectively; and finally, for γ-PCH, 2.1 mg/kg and 230 ng/m³, respectively. Twelve PNC measurements were obtained from seven different collection rooms and the diaries of the participants' activities. PNCs were highly variable between work activities. Higher personal PNCs were associated with activities like opening storage boxes with prepared animals, reading old books or handling objects. This study has shown that taxidermic objects in museum collection may be a cause for arsenic exposure during handling of objects.

Assessment of museum staff exposure to arsenic while handling contaminated exhibits by urinalysis of arsenic species

Preservation of museum objects with inorganic arsenic compounds and contamination of the surroundings has previously been documented. The present study addresses the exposure of museum staff by measuring arsenicals in urine.

After 1 week without exposure, urinary samples were taken before and after handling of preserved skins and analysed by HPLC-ICP-MS for inorganic arsenic, arsenic metabolites and arsenobetaine. The sum of inorganic arsenic and metabolites was an index of exposure. Information about work and seafood intake was obtained by questionnaire.

One out of five subjects had a work-related rise in the exposure index of 18.1 μg As/L to a post-exposure level of 37.1 μg As/L. Four subjects had no certain exposure-related increase in the index.

The study indicates that museum staff may be exposed to arsenic from handling arsenic-preserved objects and supports the use of specified arsenic analysis to avoid interference from organic arsenic.

[Morbidity and mortality in HIV infection]

Combination antiretroviral therapy (cART) has dramatically improved the prognosis of HIV-infected individuals, with a close to a normal life expectancy in a significant proportion of treated individuals. Upon start of cART, HIV-induced immune deficiency can be prevented or, if already present, reconstituted. Remaining morbidity and mortality is partly due to the late diagnosis of HIV infection or late presentation of patients, when CD4-T-cells have already fallen below 200 cells/µl and/or AIDS-defining conditions have manifested. Further reasons for remaining morbidity and mortality are related to co-morbidities such as viral hepatitis and tumors, particularly in older patients. As HIV-infected patients become older, increasing co-morbidities and socio-economic costs may become a challenge in the future.

HIV-associated central nervous system diseases in the recent combination antiretroviral therapy era

BACKGROUND AND PURPOSE

Data describing the incidence and survival of HIV-related central nervous system diseases (CNS-D) in recent years are sparse.

METHODS

Between 1996 and 2007, adult subjects without previous CNS-D within a large UK cohort were included (n=30,954). CNS-D were HIV encephalopathy (HIVe), progressive multifocal leucoencephalopathy (PML), cerebral toxoplasmosis (TOXO) and cryptococcal meningitis (CRYP). Associations between demographic, clinical and laboratory parameters with incidence and survival of CNS-D were evaluated using Poisson regression analysis and Kaplan-Meier techniques.

RESULTS

Six hundred and thirteen new CNS-D occurred in 574 subjects (HIVe:187, PML:113, TOXO:184, CRYP:129). Incidence of all CNS-D declined from 13.1 per 1000 PY in 1996/1997 to 1.0 per 1000 PY in 2006/2007 (P=0.0001). Current CD4+ cell count below 200 cells/ul and plasma HIV RNA above 100,000 copies/ml were independently associated with the development of CNS-D. Calendar year 1996/1997, older age, prior AIDS diagnosis and PML diagnosis were significantly associated with shorter survival.

CONCLUSIONS

An ongoing decline in the incidence of CNS-D has been observed in very recent years. Mortality following such a diagnosis remains high.

Oral and perioral herpes simplex virus type 1 (HSV-1) infection: review of its management

Herpes simplex virus type 1 (HSV-1) gives rise to a variety of clinical disorders and is a major cause of morbidity and mortality worldwide. HSV-1 infections are common in oral and perioral area. The aim of the present report was to critically examine the published literature to evaluate the advantages and limitations of therapy of HSV-1 infection in both immunocompetent and immunocompromised patients. Systemic antiviral therapy has been widely accepted as effective for primary herpetic gingivostomatitis. Aciclovir (ACV) 5% cream seems to be the accepted standard topical therapy for herpes labialis, being both effective and well tolerated, although penciclovir 1% cream has been proposed as a potentially useful treatment. Systemic ACV may be effective in reducing the duration of symptoms of recurrent HSV-1 infection, but the optimal timing and dose of the treatment are uncertain. Aciclovir and famciclovir may be of benefit in the acute treatment of severe HSV-1 disease in immunocompromised patients. There is also evidence that prophylactic oral ACV may reduce the frequency and severity of recurrent attack of herpetic infection in immunocompromised patients, but the optimal timing and duration of treatment is uncertain and can vary in different situations.

Human herpesvirus 8, Kaposi's sarcoma, and associated conditions

HHV-8 is a recently identified human herpes virus that can produce tumors, most often in immune compromised hosts. The virus is most closely associated with Kaposi's sarcoma, but is also clearly associated with primary effusion lymphomas and multicentric Castleman's disease. The prevalence of HHV-8 infection varies considerably, but is highest among men who have sex with men and others with histories of sexually transmitted diseases and high numbers of lifetime sexual partners. HHV-8 is shed in saliva, and less commonly in genital secretions. Treatment of HHV-8 associated diseases includes reversal of immune compromise either via discontinuation of immunosuppressives or immune reconstitution via antiretroviral regimens. Specific antiviral drug inhibit HHV-8 replication, and can result in responses in certain HHV-8-associated conditions.

Response to first protease inhibitor- and efavirenz-containing antiretroviral combination therapy. The Swiss HIV Cohort Study

OBJECTIVE

To compare the response to protease inhibitor (PI) and efavirenz-containing combination therapy among treatment-naive HIV-infected persons.

DESIGN

Prospective observational cohort study.

METHODS

Response to treatment was analysed according to the intent-to-treat principle among antiretroviral-naive patients who started either efavirenz (n = 89) or PI (n = 183) plus two nucleoside reverse transcriptase inhibitors between February 1999 and March 2000 using Kaplan-Meier and multivariable Cox proportional hazard regression methods. Primary endpoint was time to undetectable plasma viral load. Secondary endpoints included the number of CD4 cells gained, virological rebound, treatment change, and clinical progression.

RESULTS

Patients on PI regimens had lower median CD4 counts (165 versus 216 x 5 106/l; P = 0.15) and were more likely to have AIDS at initiation of treatment (25% versus 15% P = 0.048) than patients starting efavirenz regimens. The probability of reaching plasma HIV-1 RNA < 400 copies/ml was higher with efavirenz- than with PI-containing regimens [adjusted hazard ratio, 1.75; 95% confidence interval (CI), 1.34-2.29]. Median times to undetectable viral load were 58 days (95% CI, 44-70 days) for efavirenz-treated and 88 days (95% CI, 79-98 days) for PI-treated patients. The median number of CD4 cells gained in the first 6 months (90 x 10(6) cells/l with efavirenz, 10(7) x 10(6) cells/l with PI; P = 0.63), time to and reasons for treatment change, time to viral rebound, drug intolerance and clinical progression rates were similar in the two treatment groups.

CONCLUSIONS

Treatment with efavirenz-, compared with PI-based regimens, appeared to result in a superior virological response but no difference in immunological or clinical efficacy. The relevance of these observations remains to be determined in studies with longer follow-up.