What causes sepsis after BCG (Bacillus Calmette-Guérin) treatment?

From the Guidelines

BCG-induced sepsis occurs when the attenuated Mycobacterium bovis strain used in BCG therapy disseminates throughout the body, typically happening when the immune system fails to contain the bacteria at the treatment site, allowing it to spread systemically, as noted in patients with compromised immune systems, such as those with HIV/AIDS, congenital immunodeficiencies, or those taking immunosuppressive medications 1. This complication is a rare but serious side effect of BCG treatment, and its management is crucial to prevent mortality.

• The risk of BCG-induced sepsis is higher in patients receiving intravesical BCG for bladder cancer when the treatment is administered too soon after traumatic catheterization, biopsy, or when there's active urinary tract infection.
• Symptoms of BCG-induced sepsis include fever, chills, hypotension, and organ dysfunction.
• Treatment requires immediate administration of anti-tuberculosis medications, typically isoniazid, rifampin, and ethambutol, for 3-6 months, with corticosteroids added in severe cases, as recommended by the Surviving Sepsis Campaign guidelines 1.
• Prevention involves careful patient selection, ensuring bladder integrity before instillation, and avoiding BCG in patients with active urinary tract infections, recent bladder trauma, or significant immunosuppression.
• Early recognition and prompt treatment are essential to prevent mortality from this rare but serious complication, with a focus on empiric broad-spectrum therapy and subsequent de-escalation based on pathogen identification and clinical improvement 1.

From the Research

Causes of Sepsis after BCG Treatment

• BCG sepsis is a rare but potentially life-threatening side effect of intravesical BCG therapy for bladder cancer 2, 3, 4, 5, 6
• The exact cause of sepsis after BCG treatment is not fully understood, but it is thought to be related to the dissemination of BCG bacteria into the bloodstream, leading to a systemic infection 3, 4, 5
• Risk factors for developing sepsis after BCG treatment include:
  • Inadvertent intravenous administration of BCG 5
  • Immunosuppression, such as in patients with liver cirrhosis or those taking immunosuppressive medications 3, 6
  • Underlying medical conditions, such as lung disease 4
• Symptoms of sepsis after BCG treatment can include:
  • High-grade fever 3, 4, 5
  • Chills 5
  • Malaise 2
  • Bladder irritation 2
  • Respiratory failure 4
  • Septic shock 4

Treatment of Sepsis after BCG Treatment

• The treatment of choice for sepsis after BCG treatment is anti-tuberculosis therapy, including isoniazid, rifampicin, and ethambutol, with or without corticosteroids 2, 3, 4, 5
• The duration of treatment can vary depending on the severity of the infection and the patient's response to treatment, but is typically 6 months or longer 2, 3, 5
• In patients with liver cirrhosis or other underlying medical conditions, treatment may need to be adjusted to avoid hepatotoxicity or other adverse effects 3