A 29-year-old female was admitted to hospital due to eruption of papulous skin lesions on the trunk [Figure 1a and b]. As she was in the 20th week of pregnancy, a suspected diagnosis of pregnancy dermatosis was initially made. Laboratory findings were unspecific, her general well-being was not influenced at the beginning. Her younger daughter had developed similar lesions at the same time. Both had visited a swimming pool 3 days prior to the onset of the initial papules. A microbial skin swab revealed the presence of a pathogen. Histopathological examination showed an abscessing folliculitis [Figure 1c].
Figure 1.
(a and b) Erythematous papules and pustules on the right flank. (c) Histopathological findings: Periadnexal, lymphocytic infiltrate consistent with an abscessing folliculitis (HE 100x)
Question
What is your diagnosis?
Answer
Whirlpool dermatitis caused by Pseudomonas aeruginosa.
Discussion
Whirlpool dermatitis, also known as hot tub folliculitis, is a skin infection caused by the bacterium Pseudomonas aeruginosa.[1,2] This bacterium thrives in warm, moist environments, making hot tubs, whirlpools, and even swimming pools common sources of infection.[3] The condition typically occurs when individuals use facilities that are not properly sanitized or maintained, allowing the bacteria to proliferate.[2,4]
Symptoms of whirlpool dermatitis usually appear within a few hours to days after exposure of susceptible individuals.[1,3] They include red, itchy bumps or pustules around hair follicles, often resembling a rash. The rash is usually concentrated in areas covered by swimwear, as the fabric can trap the bacteria against the skin.[1] Other symptoms might include mild fever, fatigue, and discomfort as our patient developed during the course of the disease.[3]
Diagnosis is primarily clinical, based on the appearance of the rash and the patient’s recent history of hot tub or pool use.[3] In some cases, a bacterial culture may be performed to confirm the presence of Pseudomonas aeruginosa. Additionally, histopathological examination can reveal an abscessing folliculitis [Figure 1c].[3]
Most cases of whirlpool dermatitis are self-limiting and resolve within a few days to weeks without treatment. However, maintaining proper hygiene and disinfection protocols for hot tubs and pools is crucial to prevent outbreaks.[2,4] In severe or persistent cases, medical treatment with antibiotics may be necessary, considering possible multidrug resistance of the isolated pathogen.[2] Preventive measures include showering before and after using hot tubs and ensuring that such facilities are well-maintained and chlorinated.[2]
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Conflicts of interest
There are no conflicts of interest.
Funding Statement
Nil.
References
- 1.Jacob JS, Tschen J. Hot tub-associated pseudomonas folliculitis: A case report and review of host risk factors. Cureus. 2020;12:e10623. doi: 10.7759/cureus.10623. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Lutz JK, Lee J. Prevalence and antimicrobial-resistance of pseudomonas aeruginosa in swimming pools and hot tubs. Int J Environ Res Public Health. 2011;8:554–64. doi: 10.3390/ijerph8020554. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Zichichi L, Asta G, Noto G. Pseudomonas aeruginosa folliculitis after shower/bath exposure. Int J Dermatol. 2000;39:270–3. doi: 10.1046/j.1365-4362.2000.00931.x. [DOI] [PubMed] [Google Scholar]
- 4.Hopkins RS, Abbott DO, Wallace LE. Follicular dermatitis outbreak caused by pseudomonas aeruginosa associated with a Motel´s indoor swimming pool. Public Health Rep. 1974;96:246–9. [PMC free article] [PubMed] [Google Scholar]