Update on Streptococcus pneumoniae associated hemolytic uremic syndrome

Area of Science:

• Nephrology
• Infectious Diseases
• Hematology

Background:

• Streptococcus pneumoniae associated hemolytic uremic syndrome (SpHUS) presents with acute hemolytic anemia, thrombocytopenia, and acute kidney injury in patients with S. pneumoniae infection.
• SpHUS is often underdiagnosed due to overlapping features with disseminated intravascular coagulation (DIC) and a lack of strict diagnostic criteria.
• The epidemiology of SpHUS is evolving with the introduction of new pneumococcal vaccines and the emergence of different pneumococcal serotypes.

Purpose of the Study:

• To review the pathophysiology, clinical course, treatment, and prognosis of SpHUS.
• To describe an expanded classification system for identifying patients with a high likelihood of SpHUS.
• To highlight the importance of early SpHUS identification and management.

Main Methods:

• Literature review of SpHUS.
• Analysis of clinical presentation and diagnostic challenges.
• Description of a proposed expanded classification system.

Main Results:

• SpHUS accounts for 5-15% of all hemolytic uremic syndrome (HUS) cases.
• Patients with SpHUS and pneumonia generally have a lower mortality rate compared to those with meningitis.
• The Thomsen-Friedenreich antigen, exposed by S. pneumoniae neuraminidase, appears central to SpHUS pathogenesis, causing hemolysis and endothelial injury.

Conclusions:

• Early identification of SpHUS is critical for appropriate management, particularly to avoid fresh frozen plasma administration.
• Understanding the role of the Thomsen-Friedenreich antigen offers insights into SpHUS pathogenesis.
• Further research and refined diagnostic criteria are needed to improve SpHUS diagnosis and treatment.