Spa pool folliculitis
What is spa pool folliculitis?
Spa pool folliculitis is also known as "hot tub folliculitis" or "pseudomonas folliculitis". It is a skin condition that arises within hours to a few days after bathing in warm water, eg in a spa pool, jacuzzi or swimming pool. It may affect several individuals within 8 hours to 5 days of exposure. However, some exposed individuals do not develop the infection.
A similar rash may occur from wearing a wet suit that has not been thoroughly washed and dried after previous use. Pseudomonas folliculitis has also been reported in an industrial plant with a closed-loop water recycling system.
Rarely, aeromonas infection has been reported after bathing in a spa pool.
What are the symptoms of spa pool folliculitis?
Spa pool folliculitis is an eruption of scattered small red itchy or tender bumps, some of which are pustular. They mainly occur in areas that were covered by the swimming costume.
Some people with spa pool folliculitis feel unwell. They may have earache, sore throat, nausea and vomiting, headache and/or mild fever.
Spa pool folliculitis may rarely progress to a more serious infection, ecthyma gangrenosum, in people who have weak immune systems, for example those taking immunosuppressive medications.
What is the cause of the folliculitis?
Spa pool folliculitis is due to an opportunistic bacterial infection of the skin, Pseudomonas aeruginosa. This can survive in warm water, even when adequately chlorinated, because of a biofilm on the tub surface or within the piping system. Contamination is more common if the water is inadequately treated or organic material, such as skin, is present.
Concern has been expressed that the strains of bacteria that have survived chlorination may be multidrug resistant.
How is the diagnosis of spa pool folliculitis made?
The diagnosis of spa pool folliculitis is made clinically by observing a typical eruption of papules and pustules on the trunk of a person who has bathed in a hot water tub within the previous few days.
Pseudomonas aeruginosa is isolated from swabs from the pustules. Antibiotic sensitivities should be reported, as there are various isolates. Many of these are resistant to multiple antibiotics.
What is the treatment of spa pool folliculitis?
P. aeruginosa does not survive long on healthy normal skin, so spa pool folliculitis usually settles by itself within a few days.
Mild cases of spa pool folliculitis do not require treatment. Extensive or severe spa pool folliculitis due to pseudomonas infection can be treated with topical or systemic antibiotics active against Gram-negative bacteria (the Gram stain is used during microscopy or cytology of a skin swab), such as:
- Gentamicin cream
- Polymyxin B spray
- Oral ciprofloxacin
The responsible pool should be properly cleaned and disinfected with adequate chlorination or other method.
- Durdu M, Ilkit M. First step in the differential diagnosis of folliculitis: cytology. Crit Rev Microbiol. 2013 Feb;39(1):9-25. doi: 10.3109/1040841X.2012.682051. Epub 2012 May 29. Review. PubMed PMID: 22639852.
- Molina-Leyva A, Ruiz-Ruigomez M. Pseudomonas folliculitis in Arabian baths. Dermatol Online J. 2013 Jul 14;19(7):18959. PubMed PMID: 24010505.
- Lutz JK, Lee J. Prevalence and antimicrobial-resistance of Pseudomonas aeruginosa in swimming pools and hot tubs. Int J Environ Res Public Health. 2011 Feb;8(2):554-64. doi: 10.3390/ijerph8020554. Epub 2011 Feb 18. PubMed PMID: 21556203; PubMed Central PMCID: PMC3084478.
- Hewitt DJ, Weeks DA, Millner GC, Huss RG. Industrial Pseudomonas folliculitis. Am J Ind Med. 2006 Nov;49(11):895-9. PubMed PMID: 17036348.
On DermNet NZ:
- Pseudomonas folliculitis – Medscape Reference
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