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The following is a summary of “CD4/CD8 T-cell ratio in bronchoalveolar lavage fluid as a marker of sarcoidosis severity: a retrospective study,” published in the May 2025 issue of BMC Pulmonary Medicine by Zannese et al. 

Sarcoidosis was recognized as a complex multisystem disease with diverse clinical presentations and variable severity, while the prognostic value of paraclinical markers remained uncertain.  

Researchers conducted a retrospective study to evaluate the utility of the CD4/CD8 T-cell ratio (R) in bronchoalveolar lavage (BAL) fluid as a marker of sarcoidosis severity.  

They analyzed patients diagnosed with sarcoidosis by immunological analysis of BAL fluid who underwent flexible bronchoscopy with BAL between June 2010 and April 2020 at Bordeaux University Hospital. Patients diagnosed with sarcoidosis before BAL, without immunological BAL analysis, or with other diagnoses were excluded.  

The results showed that among 62 patients, half had a CD4/CD8 T-cell R ≥3.5. Those with R < 3.5 exhibited more extrapulmonary symptoms, especially abdominal involvement (32.3% vs 6.5%, P= 0.01) and a trend toward increased cardiac and central nervous system involvement (19.4% vs. 6.5%, P= 0.25). Interstitial lung disease was more common in this group (80.6% vs 67.7%, P= 0.2) alongside a tendency for worse respiratory function. Peripheral blood CD8+ T-cell activation was significantly elevated in patients with R < 3.5 (P= 0.01). Conversely, those with R ≥ 3.5 had a higher, though not significant, rate of musculoskeletal–cutaneous involvement (48.4% vs 32.3%, P= 0.2). Treatment initiation was more frequent in the R < 3.5 group (71% vs 35.5%, P= 0.01), with greater use of immunosuppressants (54.5% vs 36.4%, P= 0.02).  

Investigators concluded that an R-value < 3.5 in BAL fluid was associated with greater sarcoidosis severity, marked by worse respiratory function, broader multisystem involvement, and higher use of immunosuppressive therapy. 

Source: bmcpulmmed.biomedcentral.com/articles/10.1186/s12890-024-03428-5