Increased Risk of Lymphoma in Men or the Elderly Infected with Tuberculosis

Low-dose M.tb infection but not BCG or MTBVAC vaccination enhances heterologous antibody titres in non-human primates

Introduction

Mycobacteria are known to exert a range of heterologous effects on the immune system. The mycobacteria-based Freund's Complete Adjuvant is a potent non-specific stimulator of the immune response used in immunization protocols promoting antibody production, and Mycobacterium bovis Bacille Calmette Guérin (BCG) vaccination has been linked with decreased morbidity and mortality beyond the specific protection it provides against tuberculosis (TB) in some populations and age groups. The role of heterologous antibodies in this phenomenon, if any, remains unclear and under-studied.

Methods

We set out to evaluate antibody responses to a range of unrelated pathogens following infection with Mycobacterium tuberculosis (M.tb) and vaccination with BCG or a candidate TB vaccine, MTBVAC, in non-human primates.

Results

We demonstrate a significant increase in the titer of antibodies against SARS-CoV-2, cytomegalovirus, Epstein-Barr virus, tetanus toxoid, and respiratory syncytial virus antigens following low-dose aerosol infection with M.tb. The magnitude of some of these responses correlated with TB disease severity. However, vaccination with BCG administered by the intradermal, intravenous or aerosol routes, or intradermal delivery of MTBVAC, did not increase antibody responses against unrelated pathogens.

Discussion

Our findings suggest that it is unlikely that heterologous antibodies contribute to the non-specific effects of these vaccines. The apparent dysregulation of B cell responses associated with TB disease warrants further investigation, with potential implications for risk of B cell cancers and novel therapeutic strategies.

Non-resolving pneumonia: primary pulmonary MALT lymphoma

Mucosa-associated lymphoid tissue (MALT) lymphoma is an uncommon extranodal low-grade B-cell lymphoma. Pulmonary MALT lymphomas originate from bronchial MALT and are also referred to as bronchial-associated lymphoid tissue lymphomas. MALT lymphomas of the lung are slow-growing tumours and usually present as asymptomatic chronic alveolar opacities visible on chest radiographs or with non-specific pulmonary symptoms. Here we described a case of a male patient in his early 50s with cough and chest pain for 4 years. His CT chest scan showed consolidation in the lingula and left lower lobe. Histopathology of the specimen obtained from cryobiopsy of the lung lesion showed a dense monomorphic lymphoid infiltrate, and immunohistochemistry confirmed the diagnosis of MALT lymphoma. The prognosis of pulmonary MALT lymphomas is good with >80% 5-year survival rates. This case highlights that MALT lymphoma should be considered as a differential diagnosis while evaluating cases with non-resolving consolidation.

Recurrent choriocarcinoma complicated with leprosy during chemotherapy: A case report and literature review

RATIONALE

The global prevalence of leprosy has decreased substantially, and cases of leprosy infection are extremely rare in China. In this report, we present a case of recurrent choriocarcinoma complicated by leprosy infection during chemotherapy.

PATIENT CONCERNS

A 24-year-old Chinese woman (gravida 3, para 2) presented to a local hospital with vaginal bleeding. Her medical history included a previous diagnosis of hydatidiform mole.

DIAGNOSES, INTERVENTIONS AND OUTCOMES

The patient was diagnosed with choriocarcinoma and received chemotherapy in 6 cycles. Shortly after the initial treatment was completed, the disease recurred twice with resistance to multiple chemotherapeutic agents. In her second recurrence of choriocarcinoma, she was diagnosed with leprosy with many cutaneous nodules throughout her entire body. The patient was administered chemical treatment for leprosy with the multidrug therapy regimen after being diagnosed. To prevent exacerbating the infection, no immunotherapy was utilized to treat cancer, and the infection was well-controlled at the conclusion of anticancer therapy.

LESSONS

Because of immunological reduction, cancer patients are susceptible to a variety of infections. For patients with cancer, prevention and early detection of rare infectious diseases should receive special attention. Immunotherapy must be used with caution when treating patients with cancer and infections.

Hodgkin Lymphoma after Disseminated Mycobacterium genavense Infection, Germany

Mycobacterium genavense infection, a rare nontuberculous mycobacteria infection, occurs in heavily immunocompromised patients (i.e., those with advanced HIV disease, genetic disorders, or acquired immunologic disorders and those undergoing immunosuppressive therapy). We report a case of disseminated M. genavense infection preceding Hodgkin lymphoma in a patient without obvious risk factors for this infection.