Pat is a 31-year-old accountant who presents complaining of several months of progressively malodourous underarms.

<p>Pat is a 31-year-old accountant who presents complaining of several months of progressively malodourous underarms.</p><p>In the past few weeks he has noticed his axillary hair appears yellow-white in parts.</p><p>Pat is used to sweating a lot and self-manages with a regular antiperspirant, in addition to regular bathing and laundry.</p><p>This offensive odour is new, even though he has not changed any skin or laundry products or self-care routine.</p><p>Pat is otherwise well, with no history of note.</p><p>On examination, the axillary hair shafts are encircled by what appears to be soft yellow-white material. The hair roots, adjacent skin and other hair-bearing regions are unaffected.</p><p>On Wood’s lamp examination the concretions exhibit yellow-green, purple and red fluorescence.</p>

Dr Kate Kelso is a GP and medical editor at Australian Doctor.

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