Discussion
Infectious etiologies of folliculitis include bacteria, fungi,
parasites, and viruses. Staphylococcus aureus is the most common
infectious etiology of folliculitis. Gram negative folliculitis due toPseudomonas aeruginosa, or “hot tub folliculitis,” occurs after
exposure to contaminated water from swimming pools or hot tubs. Less
commonly recognized exposures include bath sponges, diving suits, and
cleaning gloves. Medications such as oral contraceptives, lithium,
corticosteroids, immunosuppressants, and anticonvulsants can cause
non-infectious superficial folliculitis.
Superficial folliculitis is treated with cleaning the area twice daily
with warm water and antibacterial soap and warm compresses. Deep or
recurrent episodes of folliculitis are treated with dicloxacillin or
cefalexin. Coverage for Methicillin resistant Staphylococcus
aureus (MRSA) should be considered if there is purulence, signs of
systemic infection, or risk factors for MRSA. Incision and drainage is
recommended for larger pustules or abscesses. Untreated severe or
recurrent folliculitis can lead to hair loss and scarring.
While folliculitis due to Pseudomonas aeruginosa has been well
described, sepsis due to Pseudomonas folliculitis in an immunocompetent
patient is rare and contributed to the diagnostic challenge in our
patient. Additionally, discrepancy between Gram stain and culture
results led to delay in initiating gram-negative antimicrobial coverage.
Discrepancy between Gram stain and culture results occurs in 0.4% -
2.7% of cases. Interpretation of Gram stain results are subject to
technician error depending on training level and experience. Recognition
of potential lab error in Gram stain results is important when caring
for a patient who is not responding to treatment.