The Classic Folliculitis Decalvans "Microbiological Signature"

Staphylococcus aureus may be a ‘biomarker’ of Classic FD not not LPPFDPS

The authors set out to better understand the bacterial composition of patients with folliculitis decalvans compared to those with closely related lichen planopilaris-folliculitis decalvans phenotypic spectrum (LPPFDPS).

The authors evalauted 5 patients with classic FD and 5 patients with LPPFDPS. Classic FD were said to be those patients with pustules adn crusts and yellow purulent exudate.

S. aureus in FD

In patients with the typical FD pattern, Staphylococcus bacteria in FD-affected hair follicles were statistically significantly increased compared with healthy hair follicles. There were statistically significant increased levels of S aureus were found in patients with a typical FD pattern compared with patients with FDLPPPS.

Staphylococcus aureus becomes less prevalent in LPPDS

Levels of S aureus were greater than 20% of the total follicular bacterial composition in typical FD biopsies but less than 20% in FDLPPPS patients.

Many bacteria were found to be more prevalent in FD compared to LPPFDPS

Bacilli, Staphylococcus, staphylococcaceae, Bacillales, Firmicutes were up to 5 fold more common in classic FD than LPPFDPS.

Robinsoniella, Patescibacteria, Saccharimonadaceae, Saccharimonadales, Saccharimonadia and CandidatusSachharimonas were five times more common in LPPFDPS than FD

Conclusions

The authors here proposed that staphylococcus as a bacterial biomarker of typical FD but not FDLPPPS

This is interesting study. We may need to back an re-evaluate FD vs LPPFDPS. It could be that the role of Sl aureus may be different in classic FD vs LPPDSPS. IThe authors point out that the more neutrophilic and acute stages of FD, antibiotics should be prioritized, whereas in FDLPPPS, anti-inflammatory drugs could be the first choice.

It’s not quite so simple as doxycycline is antiinflammatory and antibacterial