Primary hyperhidrosis increases the risk of cutaneous infection: A case-control study of 387 patients

Background: Although primary hyperhidrosis (PHH) has been frequently associated with diminished quality of life, the medical consequences of the condition are less well studied. Objective: The objective was to study the clinical presentation of PHH and to determine its relationship to cutaneous infection. Methods: A retrospective case-control study of patients encountered between 1993 and 2005 with the International Classification of Diseases, Ninth Revision diagnosis code for hyperhidrosis (HH) and meeting criteria for PHH was conducted. Results: Of 387 patients with PHH included, 59% were female and 41% were male; mean age was 27.3 years (range 2-72). Sites of HH included soles (50.1%), palms (45.2%), and axillae (43.4%). Distributional patterns of HH were isolated axillary (27.6%), palmoplantar (24-3%), isolated plantar (15%), axillary/ palmoplantar (5.7%), isolated palmar (5.7%), and craniofacial (5.2%). Axillary HH was more common in female patients (P=.004). The mean age of onset (18.6 +/- 12.3 years) indicated a mean duration of untreated symptoms of 8.9 years. Age at onset for palmoplantar HH (11.5 +/- 8 years) was significantly younger than for axillary HH (20.0 +/- 8.3 years; P<.0001), whereas onset of craniofacial HH (25.4 +/- 13.7 years) was older (P<.001). Exacerbating factors included stress/emotion/anxiety (56.7%) and heat/humidity (22%). The overall risk of any cutaneous infection was significantly (P<.0001) increased in HH compared with controls (odds ratio [OR] 3.2; 95% confidence interval [CI] 2.2-4.6). Site-specific risks of fungal infection (OR 5.0; 95% CI 2.6-9.8; P<.0001), bacterial infection (OR 2.61-95% CI 1.2-5.7; P=.017), and viral infection (OR 1.9; 95% CI 1.2-3.0; P=.011) were all increased. Risks of pitted keratolysis (OR 15.4; 95% CI 2.0-117; P=.0003), dermatophytosis (OR 9.8; 95% CI 3.4-27.8; P<.0001), and verruca plantaris/vulgaris (OR 2.1; 95% CI 1.3-3.6; P=.0077) were particularly increased. Association with atopic/eczematous dermatitis (OR 2.9; 95% CI 1.5-55; P=.019) was observed. Limitations: Retrospective design and single-institution study are limitations. Conclusions: Patients with HH are at high risk of secondary infection. Management of HH may have a secondary benefit of decreasing this risk. (J Am Acad Dermatol 2009;61:242-6.)