Comparative chromatography-mass spectrometry studies on the antiretroviral drug nevirapine-analytical performance characteristics in human plasma determination

A contrast between the analytical performance characteristics using gas chromatography-mass spectrometry (GC-MS) liquid chromatography-mass spectrometry (LC-MS) and liquid chromatography-ultraviolet (LC-UV) detection for the determination of the antiretroviral drug (ARV) nevirapine (NVP) in fortified human plasma after QuEChERS extraction has been made. Analytical performance characteristics, i.e. linearities, instrument detection limits (IDLs), limits of quantitation (LOQs), method detection limits (MDLs), % mean recoveries and the corresponding relative standard deviations (%RSDs) were estimated using techniques above. Using GC-MS, the correlation coefficients (r(2)) were ≥0.990, which were deemed acceptable linearities. The MDLs ranged between 11.1-29.8μg/L and 13.7-36.0μg/L using helium and hydrogen carrier gases respectively. The LOQs ranged between 16.5-66.7μg/L and 28.4-98.7μg/L using helium and hydrogen carrier gases respectively with a % mean recovery of 83% and %RSD of 4.6%. Using LC-MS and LC-UV, the correlation coefficients (r(2)) were ≥0.990. The MDLs were ranged between 3.14 and 47.1μg/L. The LOQs ranged between 2.85 and 90.0μg/L respectively. The MDLs using GC-MS, LC-MS and LC-UV were below the therapeutic range for NVP in human plasma is considered to be between 2300μg/L (Cmin) and 8000μg/L (Cmax). This study also demonstrated that helium can be substituted with hydrogen which is relatively cheaper and easily obtainable even by use of a generator.

Global research profile on monkeypox-related literature (1962-2022): A bibliometric analysis

The recent monkeypox or mpox outbreak has been a global concern. The present study evaluated the global research outputs, research trends, and topics of published research on monkeypox using a bibliometric approach. The Scopus database was searched for terms associated with "monkeypox" or "monkey pox" up until 19 November 2022. Maps and bibliometric indicators of the retrieved documents were shown and analyzed. A total of 1,422 documents were obtained from Scopus. Other than monkeypox, the most commonly used terms included epidemic, disease outbreaks, smallpox vaccine, and orthopoxvirus. In total, 90.3% of the documents were published between 2002 and 2022. The United States, the United Kingdom, and India were the top three countries in terms of productivity. Most of the institutions were from the United States. The International Journal of Surgery, the Journal of Medical Virology, and the Travel Medicine and Infectious Disease are some of the top journals currently publishing research on monkeypox. Tecovirimat, coronavirus disease 2019 (COVID-19), homosexuality, and pandemic are emerging topics related to monkeypox.

Transmission of HIV-associated tuberculosis to healthcare workers

OBJECTIVE

A retrospective investigation was made to compare the occupational risk of tuberculosis in personnel assisting human immunodeficiency virus (HIV)-infected and uninfected subjects with active tuberculosis.

DESIGN

We retrospectively reviewed 6 years of hospital activity in 3 units where HIV-infected patients with tuberculosis are hospitalized and in 2 units where non-HIV-infected tuberculosis patients are hospitalized. The risk of occupational tuberculosis in healthcare workers who assisted HIV-infected and non-HIV-infected patients with tuberculosis was investigated.

PARTICIPANTS

The risk of occupational tuberculosis in healthcare workers was studied by considering the numbers of potential source cases (hospitalized patients with tuberculosis) in the two conditions investigated (HIV-positive and HIV-negative). Both potential source cases and cases of tuberculosis in healthcare workers had to be microbiologically proven in order to be considered.

RESULTS

Seven cases of tuberculosis occurred in persons who cared for 85 HIV-infected subjects with tuberculosis, while only 2 cases occurred in staff members who took care of 1,079 HIV-negative tuberculosis patients over the same period (relative risk = 44.4; 95% confidence interval = 8.5-438).

CONCLUSIONS

Tuberculosis seems no longer to be a neglectable risk in healthcare workers assisting patients with HIV infection. Further study is urgently needed to see whether such unexpectedly high dissemination of tuberculosis also is demonstrable in the community.

Etravirine

Etravirine, formerly known as TMC 125, is a novel non-nucleoside reverse transcriptase inhibitor (NNRTI) with potent activity against HIV resistant to currently licensed NNRTIs. It is in its final stage of clinical development and has received fast-track status for review by the U.S. Food and Drug Administration (FDA). In randomized placebo-controlled trials in treatment-experienced patients with confirmed NNRTI resistance, it has shown virological efficacy superior to the control arms with comparable rates of adverse events with the exception of rash. Because of its effect on the cytochrome P450 system, there are significant drug interaction issues that will need to be taken into consideration with its use.

Successful treatment of persistent SARS-CoV-2 infection with nirmatrelvir/ritonavir plus sotrovimab in four immunocompromised patients

Immunocompromised patients with leukemia/lymphoma often have a suboptimal response to vaccination against SARS-CoV-2 and, if infected, can develop a persistent infection.SARS-CoV-2 PCR was performed on nasopharingeal swabs and serum IgG anti-SARS-CoV-2 trimeric spike glycoprotein antibodies were measured during persistence of infection. Treatment with a combination of nirmatrelvir/ritonavir plus sotrovimab led to viral clearance in three patients with leukaemia or lymphoma with persistent SARS-CoV-2 and negative SARS-CoV-2 antibody tests. No standardized treatments for persistent infection with SARS-CoV-2 infection are available. We have reported the viral clearance in two immunocompromised patients treated with antiviral drug nirmatrelvir/ritonavir and monoclonal antibody sotrovimab. We suggest that this strategy should be tested in clinical trials to find the right strategy for a clinical problem with public health implications to SARS-CoV-2 evolution and immune escape in these sub-set of patients.

Sequential studies of pre-S2 antigenemia and anti-pre-S2 antibodies in relation to viral replication in acute hepatitis B followed from the early incubation phase

To determine the time sequence of expression of pre-S2 peptide (120-150) during the presymptomatic phase of acute hepatitis B, we used a monoclonal antibody radioimmunoassay in five subjects followed from 30 to 70 days before the onset of liver damage. Pre-S2 peptide was present in serum at low levels from the early incubation phase and started to increase immediately after the first detection of HBV-DNA in serum, in parallel with the increase in HBsAg levels. During the symptomatic phase, levels of pre-S2 peptide declined rapidly; it was no longer detectable after recovery. Anti-pre-S2 antibodies were detected, in four patients, only in the recovery phase. These results demonstrate that expression of pre-S2 peptide occurs very early in the incubation phase of acute HBV infection and is cleared in parallel with HBsAg. Anti-pre-S2 antibodies seem to play no role in viral clearance in these patients.

Response of uncomplicated falciparum malaria to oral chloroquine and quinine in Burundi highlands

The in vivo response of falciparum malaria to oral chloroquine and quinine was evaluated in two identical hospital-based, comparative open trials carried out 2 years apart in the same seasonal period at a hospital located in the highlands of Northern Burundi. Children aged 0-14 with uncomplicated falciparum malaria were administered either chloroquine, at 25 mg/kg over 3 days, or quinine, at 10 mg/kg per 8 hourly for 5 days (alternate allocation) and treatment response was evaluated by the WHO 7-day test. In the first study (1992/1993) 472 patients qualified for analyses (211 in the chloroquine and 261 in the quinine group), as compared to 249 subjects in the second study (1994/1995). In each study, the response to quinine was significantly higher than that to chloroquine (P = 0.004 and < 0.001, respectively). While the response to quinine showed insignificant changes over time (95.8 vs. 92.9%), chloroquine was found to be significantly less effective in the second study as compared to the first (77.8 vs. 63.1%; OR (95% CI) 2.04 (1.21-3.43)). Such decline in chloroquine efficacy was attributable to the age group < 5 years of age, where response to chloroquine decreased from 72.9% in 1992/93 to 56% in 1994/1995. Uncontrolled chloroquine use, which spread after the onset in late 1993 of the still ongoing ethnic fighting, appears to be the most likely reason for such a decrease in chloroquine efficacy. Chloroquine resistance has long been known to be present in the hyperendemic lowlands of Burundi, but no data have so far been reported on the response to antimalarials in the highlands of the country. These findings should be considered when deciding on drug policies for the treatment of falciparum malaria in Burundi.

Recovery of long-term natural protection against reactivation of CMV retinitis in AIDS patients responding to highly active antiretroviral therapy

OBJECTIVES

To see whether in severely immunosuppressed AIDS patients (with prior Cytomegalovirus retinal disease) who have significant increases in CD4+ lymphocytes following the initiation of highly active antiretroviral therapy (HAART) anti-Cytomegalovirus (CMV) maintenance therapy can be withdrawn with no subsequent progression of CMV retinitis.

METHODS

Eight patients with AIDS and one or more previous episodes of CMV retinitis interrupted anti-CMV maintenance therapy following the successful beginning of HAART. CD4 cell counts and HIV-RNA were monitored monthly while measurement of CMV antigenemia and ophthalmoscopy were carried every 2 weeks thereafter.

RESULTS

The HAART recipients in whom anti-CMV maintenance therapy had been interrupted had measureable increases of CD4+ T lymphocytes, substantial control of both HIV-RNA and CMV viraemia and did not show recurrence of retinitis during a mean follow-up of 98.4 weeks (range 78-120, SD 15.2).

CONCLUSIONS

Anti-CMV maintenance therapy can be interrupted with no subsequent progression of retinal damage over a long time in patients with AIDS who successfully respond to HAART with a significant increase in CD4 cell count.