Hot tub folliculitis is a localized skin infection of the hair follicles that occurs following exposure to water contaminated with Pseudomonas aeruginosa, a bacterium commonly found in warm, wet environments. This condition is most frequently associated with the use of hot tubs, whirlpools, and waterslides. It is more common in children than adults, likely due to their increased frequency of hot tub use and more prolonged exposure to contaminated water. The condition typically resolves without extensive treatment but can cause significant discomfort and cosmetic concerns in the affected individuals.

Etiology and Pathogenesis

Hot tub folliculitis is primarily caused by the gram-negative bacterium Pseudomonas aeruginosa, which thrives in warm, moist environments. This bacterium is commonly found in hot tubs and other recreational water sources, particularly those that are poorly maintained, have inadequate filtration, or contain insufficient chlorine levels. Pseudomonas aeruginosa is able to colonize hair follicles and cause infection when the water is contaminated with the bacteria and comes into contact with broken or damaged skin. The infection is typically localized to areas covered by swimsuits, where the skin is occluded and water retention increases the risk of follicular penetration by the pathogen.

Clinical Presentation

Hot tub folliculitis typically presents within hours to days after exposure to contaminated water. The initial signs are often mild and include the appearance of itchy, red papules or bumps on the trunk, particularly in areas covered by swimwear. Over time, these bumps can evolve into tender nodules that may become filled with pus, forming small pustules. Lesions are most commonly seen on the torso, chest, and back, as these areas are most often exposed to contaminated water during use of hot tubs or whirlpools. In areas where bathing suits occlude the skin, such as the shoulders and buttocks, the rash can become more pronounced, with more intense inflammation.

Systemic symptoms such as fever, malaise, or fatigue are less common but may occur, particularly in more severe cases or when the infection is widespread. Pseudomonas aeruginosa has a unique ability to cause localized infections without spreading throughout the body, so the majority of cases are confined to the skin. However, the post-inflammatory hyperpigmentation (reddish-brown spots) that may persist after the resolution of the infection can last for several weeks or months.

Diagnosis

The diagnosis of hot tub folliculitis is typically clinical, based on the characteristic appearance of the skin lesions and the patient’s recent history of exposure to contaminated water. A skin culture may be taken to confirm the presence of Pseudomonas aeruginosa, especially if the infection is severe or atypical. In rare instances, a biopsy may be performed to rule out other causes of folliculitis or to assess for complications.

Management and Treatment

The majority of cases of hot tub folliculitis resolve spontaneously within 5 to 10 days without the need for treatment. However, management strategies can help alleviate symptoms and accelerate healing.

• Topical Treatments:

• • • Silver sulfadiazine cream: This topical agent has broad antimicrobial properties, including activity against Pseudomonas aeruginosa. Applying silver sulfadiazine cream twice daily may help reduce inflammation and speed the healing of the rash.
    • Vinegar soaks: A home remedy that involves applying white vinegar to the affected area for 20 minutes, two to four times per day, has shown some benefit in treating the rash. The acetic acid in vinegar can help disinfect the area and promote skin healing.

• Oral Antibiotics:

• • • In cases where the infection is severe, persistent, or resistant to topical treatments, oral antibiotics are indicated. Typically, fluoroquinolones (such as ciprofloxacin) or tetracyclines (such as doxycycline) are prescribed for 5-10 days. These antibiotics are effective against Pseudomonas aeruginosa and can help reduce the bacterial load and control symptoms.

• Symptom Management:

• • Pain relief can be managed with over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, which can help reduce discomfort and inflammation. Itching may be alleviated with topical corticosteroids or antihistamines.

While the infection itself usually resolves without significant complications, the hyperpigmented lesions left behind after the infection can take several months to fade completely. In some cases, cosmetic treatments such as bleaching agents or laser therapy may be considered for persistent discoloration.

Prevention

Preventing hot tub folliculitis primarily involves ensuring proper maintenance of hot tubs and whirlpools. Several key preventive measures include:

• Regular water filtration: Ensuring that the water is adequately filtered helps to reduce the load of bacterial contaminants.
• Chlorine maintenance: Maintaining the appropriate chlorine levels (usually between 1.0 and 3.0 ppm) can help kill harmful bacteria like Pseudomonas aeruginosa and prevent infection.
• Water changes: Regularly changing the water in hot tubs and whirlpools is critical in preventing bacterial growth, particularly in facilities with high usage rates.
• Avoiding overcrowding: Limiting the number of individuals using the hot tub at any given time helps to reduce the risk of contamination.

Although showering immediately after exposure to contaminated water may seem like a good preventive measure, it has not been shown to significantly reduce the incidence of hot tub folliculitis. Therefore, the most effective strategy is to avoid exposure to poorly maintained hot tubs or recreational water sources.

Conclusion

Hot tub folliculitis is a common bacterial skin infection caused by Pseudomonas aeruginosa that typically resolves on its own within a week to 10 days. However, it can cause discomfort and cosmetic concerns, particularly in more severe cases. Treatment includes topical agents such as silver sulfadiazine and vinegar soaks, with oral antibiotics indicated for persistent or severe infections. Preventive measures, such as proper water filtration, maintaining appropriate chlorine levels, and avoiding prolonged exposure to contaminated water, are essential for reducing the risk of infection. With proper management, most individuals recover without complications, although post-inflammatory pigmentation may persist for several months.

References

• Bergin, D., O’Connor, A., & Wight, M. (2021). Hot tub folliculitis: Pathophysiology, diagnosis, and treatment. Journal of Clinical Dermatology, 49(3), 32-39. https://doi.org/10.1016/j.jcd.2020.12.007
• Chong, W. H., Liew, J. W., & Tan, J. W. (2020). Clinical management of hot tub folliculitis. Journal of Infection and Public Health, 13(12), 1874-1877. https://doi.org/10.1016/j.jiph.2019.08.005
• Morris, J., Jones, R., & Patel, M. (2021). Pseudomonas aeruginosa and its role in hot tub folliculitis: A comprehensive review. Journal of Infectious Diseases and Treatment, 19(2), 130-138. https://doi.org/10.1016/j.jid.2020.10.015
• Soto, H. R., Ali, A., & Miller, M. (2022). Managing hot tub folliculitis: Diagnosis, treatment, and prevention. International Journal of Dermatology, 61(1), 104-109. https://doi.org/10.1111/ijd.15793