Bone marrow infection with bacillus Calmette-Guérin (BCG) after intravesical immunotherapy

The spleen assumes a major role in blood glucose regulation in type 1 diabetes patients treated with BCG

The Bacillus Calmette-Guérin (BCG) vaccine, which has been used for > 100 years to prevent tuberculosis, is well-established for bladder cancer treatment, and under study for neurological and autoimmune diseases. In patients with type 1 diabetes (T1D), BCG vaccinations have been shown in randomized clinical trials to gradually lower blood sugar to near normal levels. This effect appears to be driven by a BCG-induced shift in lymphoid cells' glucose metabolism from oxidative phosphorylation to aerobic glycolysis. The latter is a state of high glucose utilization that draws more glucose from the blood. Apart from blood, it is unknown whether BCG establishes residence in any organs and alters their glucose metabolism. In this two-year-long clinical trial in type 1 diabetics, we use positron emission tomography (PET) and x-ray computed tomography (CT) to map organs that increase their uptake of the glucose analogue 18F-fluorodeoxyglucose (18F-FDG) before versus after BCG vaccinations. We also injected BALB/c mice with BCG to test for the presence of BCG in various organs. Results from both studies point to the spleen as the dominant site for glucose uptake and BCG residence. The human spleen is significant because its 47% increase in 18F-FDG uptake by a large population of lymphocytes and monocytes might help to explain BCG's systemic lowering of blood glucose to near normal levels. Findings suggest that the spleen, triggered by BCG, assumes a critical role in systemic glucose regulation in the absence of a functional pancreas.

Vaccines and Dementia: Part I. Non-Specific Immune Boosting with BCG: History, Ligands, and Receptors

Vaccines such as Bacille Calmette-Guérin (BCG) can apparently defer dementia onset with an efficacy better than all drugs known to date, as initially reported by Gofrit et al. (PLoS One14, e0224433), now confirmed by other studies. Understanding how and why is of immense importance because it could represent a sea-change in how we manage patients with mild cognitive impairment through to dementia. Given that infection and/or inflammation are likely to contribute to the development of dementias such as Alzheimer's disease (Part II of this work), we provide a historical and molecular background to how vaccines, adjuvants, and their component molecules can elicit broad-spectrum protective effects against diverse agents. We review early studies in which poxvirus, herpes virus, and tuberculosis (TB) infections afford cross-protection against unrelated pathogens, a concept known as 'trained immunity'. We then focus on the attenuated TB vaccine, BCG, that was introduced to protect against the causative agent of TB, Mycobacterium tuberculosis. We trace the development of BCG in the 1920 s through to the discovery, by Freund and McDermott in the 1940 s, that extracts of mycobacteria can themselves exert potent immunostimulating (adjuvant) activity; Freund's complete adjuvant based on mycobacteria remains the most potent immunopotentiator reported to date. We then discuss whether the beneficial effects of BCG require long-term persistence of live bacteria, before focusing on the specific mycobacterial molecules, notably muramyl dipeptides, that mediate immunopotentiation, as well as the receptors involved. Part II addresses evidence that immunopotentiation by BCG and other vaccines can protect against dementia development.

Culture-proven disseminated Mycobacterium Bovis infection (BCG-Osis) following intravesical BCG immunotherapy in a patient with bladder carcinoma-in-situ: ‘Case report’

We are reporting a case of culture-proven disseminated Mycobacterium Bovis infection (BCG-Osis), involving lung, bone-marrow and urinary tract, after intravesical Bacillus Calmette–Guérin (BCG) immunotherapy for bladder carcinoma-in-situ. A 71-year-gentleman presented with fever shortly after intravesical BCG instillation. He was initially treated for presumed Urinary Tract Infection, but negative urine culture and persistent fever prompted us to consider alternative diagnoses. Empirical treatment for BCG-Osis was commenced after initial negative workup including blood culture, echocardiography, computed tomography (CT) Chest, and Kidney-Ureter-Bladder (KUB). However, he remained febrile and leukopenic, so bone-marrow examination was performed along with repeating CT Chest, which revealed non-caseating granulomas and small nonspecific pulmonary nodules, respectively, supporting our provisional diagnosis. Interestingly, Mycobacterium Bovis was finally isolated from one of his urine specimens, confirming our diagnosis.

Transitory Spontaneous Remission of Myelodysplasia in an Elderly Man while Receiving Intravesical Bacillus Calmette-Guérin for Bladder Cancer: A Case Report and Review of the Literature

Myelodysplasia is a clonal disorder characterized by progressive cytopenias. Intravescial BCG is standard immunotherapy for superficial bladder cancer. We present a patient with transfusion-dependent myelodysplasia whose blood counts normalized during treatment with intravesical BCG for bladder cancer. After finishing treatment, the patient became transfusion dependent once more. We discuss possible mechanisms to explain this case report.

Bacillus Calmette-Guérin (BCG) infection following intravesical BCG administration as adjunctive therapy for bladder cancer: incidence, risk factors, and outcome in a single-institution series and review of the literature

Bacillus Calmette-Guérin (BCG) is the most effective intravesical immunotherapy for superficial bladder cancer. Although generally well tolerated, BCG-related infectious complications may occur following instillation. Much of the current knowledge about this complication comes from single case reports, with heterogeneous diagnostic and therapeutic approaches and no investigation on risk factors for its occurrence. We retrospectively analyzed 256 patients treated with intravesical BCG in our institution during a 6-year period, with a minimum follow-up of 6 months after the last instillation. We also conducted a comprehensive review and pooled analysis of additional cases reported in the literature since 1975. Eleven patients (4.3%) developed systemic BCG infection in our institution, with miliary tuberculosis as the most common form (6 cases). A 3-drug antituberculosis regimen was initiated in all but 1 patient, with a favorable outcome in 9/10 cases. There were no significant differences in the mean number of transurethral resections prior to the first instillation, the time interval between both procedures, the overall mean number of instillations, or the presence of underlying immunosuppression between patients with or without BCG infection. We included 282 patients in the pooled analysis (271 from the literature and 11 from our institution). Disseminated (34.4%), genitourinary (23.4%), and osteomuscular (19.9%) infections were the most common presentations of disease. Specimens for microbiologic diagnosis were obtained in 87.2% of cases, and the diagnostic performances for acid-fast staining, conventional culture, and polymerase chain reaction (PCR)-based assays were 25.3%, 40.9%, and 41.8%, respectively. Most patients (82.5%) received antituberculosis therapy for a median of 6.0 (interquartile range: 4.0-9.0) months. Patients with disseminated infection more commonly received antituberculosis therapy and adjuvant corticosteroids, whereas those with reactive arthritis were frequently treated only with nonsteroidal antiinflammatory drugs (p < 0.001 for all comparisons). Attributable mortality was higher for patients aged ≥65 years (7.4% vs 2.1%; p = 0.091) and those with disseminated infection (9.9% vs 3.0%; p = 0.040) and vascular involvement (16.7% vs 4.6%; p = 0.064). The scheduled BCG regimen was resumed in only 2 of 36 patients with available data (5.6%), with an uneventful outcome. In the absence of an apparent predictor of the development of disseminated BCG infection after intravesical therapy, and considering the protean variety of clinical manifestations, it is essential to keep a high index of suspicion to initiate adequate therapy promptly and to evaluate carefully the risk-benefit balance of resuming intravesical BCG immunotherapy.

Fever of unknown origin and pancytopenia caused by culture-proven delayed onset disseminated bacillus Calmette-Guerin (BCG) infection after intravesical instillation

A 78-year-old man was diagnosed with bladder carcinoma in situ and was successfully treated with intravesical bacillus Calmette-Guérin (BCG) instillations. At 6 months after the last dose, he developed fever, weight loss and malaise. He had an extensive negative workup at an outside hospital and was treated empirically with ciprofloxacin for 2 weeks. The fever resolved but returned months later and he was readmitted with pancytopenia, elevated alkaline phosphatase and ground glass opacities on the chest CT. Bone marrow and liver biopsies showed non-caseating granulomas and were negative for acid-fast bacillus (AFB) and fungal stains. Mycobacterium tuberculosis complex PCR of the bone marrow was negative. Owing to the high clinical suspicion of disseminated BCG infection, the patient was treated empirically. After 9 weeks of incubation, the bone marrow AFB culture grew Mycobacterium bovis. Within 2 months of treatment his symptoms resolved and his laboratory results normalised.