Management of Infection in SLE

Approach to Fever in SLE

• Difficult to differentiate between lupus flare and active infection
• Systemic lupus is also reported as a cause of fever of unknown origin (FUO)  (at least 1/3 of all causes)
• Adjustment of lupus treatment or initiation of a trial of empiric antibiotics should be determined based on the initial findings and patient status
• In newly diagnosed patients, if steroids produces a rapid disappearance of fever, its SLE Flare; when fever persists, the search of an infectious source is mandatory
• No specific biomarkers to differentiate between both

Common causative organism

Bacterial

• Pneumonia and respiratory tract infections are the most recognized
• S. aureus and Streptococcus pyogenes persist as the most frequent etiology of respiratory infections
• In outpatient setting, common gram-negative bacteria are Klebsiella sp, Pseudomonas aeruginosa, and E. coli
• Streptococcus pneumoniae has been reported as a cause of septicemia;(lower rate after routine vaccination)
• Urinary tract infections are very common among women with SLE commonly due to  E coli and Streptococcus agalactiae 
• Infections due to Salmonella species are important cause of bacteremia after ingestion of contaminated food

Mycobacterium

• Infections as a consequence of Mycobacterium species are of two groups
• infections due to M tuberculosis, that trend to occur early in the course of lupus, related to disease activity and treatment, and usually resulting mainly from reactivation of latent infection or to reinfection
• infections to non-tuberculous Mycobacterium (NTM), presenting later in the course of disease and predominantly as a new infection, including M. avium complex, M. chelonae, M. haemophilum or M. fortitum

Viral

• SLE was the most important risk factor to develop Herpes Zoster at population level
• Epstein-Barr virus (EBV) infection importance resides in its temporal relationship with lupus initiation
• Coexistence of SLE and HCV infection is therefore not an unusual treat
• Other viral infections in lupus patients such as mumps, measles, herpesvirus-6, or herpes simplex virus are seldom reported and seem not to have relevance interactions of these viral agents and SLE

Fungal

• Candida species, which may affect pharynx, esophagus, and the urinary tract or may present themselves as a primary bloodstream infection
• fatal cases of lupus patients with meningeal infection are caused by C. neoformans 

Reference:

Infection and systemic Lupus Erythematous. www.inthechopen.com