Disseminated mycobacterium avium-intracellulare complex (MAC) infection in the era of effective antiretroviral therapy: is prophylaxis still indicated?

Disseminated MAI in an HIV Patient-An Unusual Presentation

Patients with Human Immunodeficiency Virus (HIV), and especially Acquired Immunodeficiency Syndrome (AIDS), can present in a multitude of ways with a variety of possible pathologies. This can prove to be a challenge to a clinician. The patient, in this case, was found to have disseminated Mycobacterium-avium-intracellulare (MAI), despite compliance with antiretroviral therapy (ART), who presented with right upper quadrant pain, isolated elevated alkaline phosphatase, and sepsis. Imaging revealed multiple splenic lesions, bilateral psoas abscesses, abdominal lymphadenopathy, and a large right pleural effusion with a mediastinal shift to the left. Psoas abscesses were drained and the cultures grew acid-fast bacilli. The patient was treated with azithromycin, ethambutol and rifabutin. Classically, MAI infections of patients compliant with ART therapy present with localized disease. This case offers a different presentation of MAI despite compliance with ART therapy.

Disseminated disease due to non-tuberculous mycobacteria in HIV positive patients: A retrospective case control study

Introduction

Disseminated infection due to non-tuberculous mycobacteria has been a major factor of mortality and comorbidity in HIV patients. Until 2018, U.S. American guidelines have recommended antimycobacterial prophylaxis in patients with low CD4 cell counts, a practice that has not been adopted in Europe. This study aimed at examining the impact of disseminated NTM disease on clinical outcome in German HIV patients with a severe immunodeficiency.

Materials and methods

In this retrospective case control study, HIV patients with disseminated NTM disease were identified by retrospective chart review and matched by their CD4 cell counts to HIV patients without NTM infection in a 1:1 alocation. Primary endpoints were mortality and time to first rehospitalisation. In addition, other opportunistic diseases, as well as antimycobacterial and antiretroviral treatments were examined.

Results

Between 2006 and 2016, we identified 37 HIV patients with disseminated NTM disease. Most of them were suffering from infections due to M. avium complex (n = 31, 77.5%). Time to event analysis showed a non-significant trend to higher mortality in patients with disseminated NTM disease (p = 0.24). Rehospitalisation took place significantly earlier in patients with disseminated NTM infections (median 40.5 days vs. 109 days, p<0.0001).

Conclusion

In this retrospective case control study, we could demonstrate that mortality is not significantly higher in HIV patients with disseminated NTM disease in the ART era, but that they require specialised medical attention in the first months following discharge.

Patterns of Mycobacterium avium-intracellulare complex infection in duodenal endoscopic biopsies in HIV/AIDS patients

Mycobacterium avium-intracellulare complex (MAIC) is a nontuberculous opportunistic infection in immunocompromised patients. Involvement of the gastrointestinal tract (GIT) is usually part of a disseminated disease in AIDS patients with a low CD4 count, however with standard antiretroviral therapy (ART), a localized presentation is more likely. It can affect any part of the GIT, mostly the duodenum and typically as patches. Incomplete or refractory ART for HIV-strains, therapy-related side effects, noncompliant or incomplete treatment to previous MAIC infections, superimposed complications and comorbid opportunistic infections may result in atypical clinical, endoscopic and histopathologic manifestations. We performed a retrospective review study retrieving cases of MAIC in duodenal endoscopic biopsy. We found five cases of MAIC in HIV/AIDS patients. They were males with an average age of 40-years. They showed different histopathologic features, variable patterns of MAIC-histiocytic infiltrates, and varying intensity of intracellular acid-fast positive bacilli. Enterocytes vacuolization and transepithelial elimination were also observed. Three cases were associated with cytomegalovirus and cryptococcal infections. A case was complicated by lymphangiectasia-associated protein-losing enteropathy. Initially, three cases were morphologically missed. Ziehl-Neelsen stain helped reach the correct diagnosis. Pathologists have an important role in patients' management by guiding clinicians to the correct diagnosis. Pathologists should be aware of these different histopathologic manifestations, their potential pitfalls, look for certain helpful clues complemented with multiple levels and special stains. In particular, AFB stains are mandatory in all mucosal biopsy specimens from HIV/AIDS patients regardless of their appearances.

Incidence of disseminated Mycobacterium avium-complex infection in HIV patients receiving antiretroviral therapy with use of Mycobacterium avium-complex prophylaxis

The incidence of disseminated Mycobacterium avium complex (MAC) infection in HIV patients has fallen markedly since the introduction of effective antiretroviral therapy (ART). However, current guidelines still recommend primary prophylaxis. We conducted a retrospective cohort study in a university-affiliated hospital from January 1998 to January 2014. During that period, HIV patients who had at least one CD4 cell count below 50 cells/mm³ and had been treated with ART were enrolled. We compared incidence of disseminated MAC infection in the 12 months after the first CD4 cell count below 50 cells/mm³ between prophylaxis and nonprophylaxis groups. A total of 157 patients were enrolled and the total observation period was 144 patient-years (PY). Thirty-three patients (21%) received primary MAC prophylaxis. The initial CD4 cell count of the prophylaxis group was lower than that of the nonprophylaxis group ( P = 0.024), but the proportion of patients who reached a CD4 cell count >100 cells/mm³ ( P = 0.234) and were virologically suppressed ( P = 0.513) 12 months after ART commencement was not different in the prophylaxis and nonprophylaxis groups. The incidence of MAC did not differ significantly between the groups (3.4/100 PY versus 0.8/100 PY, P = 0.368). Routine MAC prophylaxis may be not required in the era of effective ART.

Mycobacterium avium-Intracellulare Complex (MAC) Producing a Periportal Pseudotumor in a Patient With HIV and a Normal CD4 Count

Mycobacterium avium-intracellulare complex (MAC) is an opportunistic infection typically associated with profound immunosuppression, such as AIDS. The presentation of disseminated MAC can be subtle and mimic systemic symptoms associated with lymphoma; abdominal pseudotumor is an exceptionally rare presentation. In the era of highly active anti-retroviral therapy (HAART), opportunistic infections are increasingly rare, and secondary prophylaxis for MAC may be discontinued after adequate therapy and immune reconstitution. Recurrence of disseminated MAC after adequate therapy may be due to macrolide resistance, but with an adequate CD4 T-cell count and undetectable HIV viral load, recurrence raises questions of more subtle immune dysregulation.

High recurrence rate supports need for secondary prophylaxis in non-HIV patients with disseminated mycobacterium avium complex infection: a multi-center observational study

Background

Long-term outcomes in non-HIV immunocompromised patients with disseminated Mycobacterium avium complex (dMAC) infections are unknown and the need for post-treatment secondary prophylaxis against MAC is uncertain in this setting. The objective of this study was to determine the need of continuing secondary anti-MAC prophylaxis in non-HIV patients after completing treatment of the primary dMAC episode.

Methods

We conducted a ten-year multi-center analysis of non-HIV immunosuppressed patients with dMAC infections in Hong Kong.

Results

We observed sixteen patients with dMAC during the study period of which five (31 %) were non-HIV immunosuppressed patients. In the non-HIV immunosuppressed group, three patients completed a treatment course without secondary prophylaxis, one patient received azithromycin-based secondary prophylaxis and one patient was still receiving therapy for the first dMAC episode. All the three patients who completed treatment without being given secondary prophylaxis developed recurrent dMAC infection requiring retreatment.

Conclusions

In view of the high rate of dMAC infection recurrence in non-HIV immunocompromised patients following treatment completion, our data support long-term anti-MAC suppression therapy after treatment of the first dMAC infection episode in immunocompromised non-HIV patients, as is recommended for patients with advanced HIV. Tests of cell mediated immune function need to be evaluated to guide prophylaxis discontinuation in non-HIV patients.

Therapy and prophylaxis of opportunistic infections in HIV-infected patients: a guideline by the German and Austrian AIDS societies (DAIG/ÖAG) (AWMF 055/066)

INTRODUCTION

There was a growing need for practical guidelines for the most common OIs in Germany and Austria under consideration of the local epidemiological conditions.

MATERIALS AND METHODS

The German and Austrian AIDS societies developed these guidelines between March 2010 and November 2011. A structured Medline research was performed for 12 diseases, namely Immune reconstitution inflammatory syndrome, Pneumocystis jiroveci pneumonia, cerebral toxoplasmosis, cytomegalovirus manifestations, candidiasis, herpes simplex virus infections, varizella zoster virus infections, progressive multifocal leucencephalopathy, cryptosporidiosis, cryptococcosis, nontuberculosis mycobacteria infections and tuberculosis. Due to the lack of evidence by randomized controlled trials, part of the guidelines reflects expert opinions. The German version was accepted by the German and Austrian AIDS Societies and was previously published by the Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF; German Association of the Scientific Medical Societies).

CONCLUSION

The review presented here is a translation of a short version of the German-Austrian Guidelines of opportunistic infections in HIV patients. These guidelines are well-accepted in a clinical setting in both Germany and Austria. They lead to a similar treatment of a heterogeneous group of patients in these countries.

Survival of Mycobacterium avium attached to polyethylene terephtalate (PET) water bottles

AIMS

The main objective of our study was to assess the persistence of Mycobacterium avium in an oligotrophic environment such as bottled groundwater.

METHODS AND RESULTS

Filtered groundwater samples were spiked with washed Myco. avium suspension and stored in dark and under static conditions, at 20 degrees C, for 3 months in 500 ml PET bottles. The loss of Myco. avium cultivability was slow in water. On the contrary, after a 3-month storage at 20 degrees C, growth of attached cells was observed and cell adhesiveness to the PET wall increased with time. It could probably be because of the presence of an extracellular matrix.

CONCLUSIONS

This study has shown the great stability of Myco. avium in bulk water as well as their adhesiveness and their growth on a PET bottle wall in an oligotrophic environment.

SIGNIFICANCE AND IMPACT OF THE STUDY

Slowly growing mycobacteria are well adapted to oligotrophic environments such as groundwater. As they stick very well to surfaces, they could be used for determining the efficiency of the cleaning of contaminated surfaces.

Fatal dual infection with Salmonella and Mycobacterium avium complex infection in a patient with advanced acquired immunodeficiency syndrome: a case report

Non-typhoid Salmonella and Mycobacterium avium complex infections are part of the constellation of infections seen with increasing frequency in patients with acquired immuned deficiency syndrome. The incidence has reduced significantly since highly active antiretroviral therapy era, but their critical nature is unchanged. The co-existence of these infections and the accompanied increased mortality is presented in this case report.

In vitro antimycobacterial activity of newly synthesised S-alkylisothiosemicarbazone derivatives and synergistic interactions in combination with rifamycins against Mycobacterium avium

The antimycobacterial activities of two new S-alkylisothiosemicarbazone derivatives (1i and 1f) against 32 Mycobacterium avium isolates were investigated. The minimum inhibitory concentrations (MICs) were significantly lower than those of rifampicin and other reference drugs. The two derivatives also showed excellent intracellular activity against M. avium residing in the macrophage-like J774 cells. Interestingly, the combination of subinhibitory concentrations of 1i and rifabutin or rifampicin induced a potent synergistic effect, as determined by the fractional inhibitory concentration indexes (FICIs) ranging between 0.103 and 0.412. Such synergistic effect resulted in a 81-fold and 139-fold reduction of the MICs of rifabutin and rifampicin, respectively. Enhancement of intracellular activity of rifabutin by the S-alkylisothiosemicarbazone derivative 1i was also observed. Results indicate that S-alkylisothiosemicarbazones can be useful in the therapy and prophylaxis of M. avium infections and can represent a template for the development of novel antimycobacterial drugs. Furthermore, as a consequence of their ability to enhance the activity of rifamycins, a reduction of drug interactions following the co-administration of protease inhibitors could be achieved by lower doses of rifampicin and rifabutin.