A Case of Acute Generalised Exanthematous Pustulosis after Unprotected Sexual Intercourse on Holidays in Bali
A 43-year-old man presented to a rural hospital in Australia for lethargy, fever, arthralgia, chills, peri-orbital oedema and an erythematous pustular rash increasing in size over his hands, back, chest and face for approximately 48 h. He was a fly-in fly-out worker in the catchment area of the hospital. He mentioned holidaying in Bali, Indonesia, for 9 days to visit a female partner with whom he had unprotected sexual intercourse. The symptoms started promptly upon his return. All in all, he had visited his partner five times this calendar year. He reported to have contracted genital herpes from this partner on his first visit and had sought treatment with antivirals (acyclovir) upon his return to Australia and had remained on them ever since. He also mentioned that both he and his partner had been monogamous since the day they met each other. Furthermore, he described some recent coryzal symptoms towards the end of his holiday, for which he bought some local cold and flu medication, the name and ingredients of which being unknown but being somewhat ‘like Sudafed®’. He also took some Nurofen® tablets (ibuprofen) in Bali and upon returning to Australia. Apart from cystic acne 25 years ago and intermittently taking ibuprofen, the patient reported no significant past medical history.\nAt this rural hospital, he continued to decline systemically (fever >39.5°C, heart rate >125 bpm) over 36 h and was flown to a tertiary referral hospital in Brisbane. On arrival, he had widespread pustules on his face, neck, back, chest, upper and lower limbs (fig. , fig. , fig. ). It was noted that he was also erythematous and had an oedematous face. He described only a mild itch and denied any genitourinary symptoms. Some inguinal and cervical lymphadenopathy and minimal oral involvement were observed. He had a raised white blood cell count (13.2), neutrophilia (12.17), a mild lymphocytosis (0.56), a raised C-reactive protein level (273), and was started immediately on intravenous piperacillin/tazobactam three times daily, intravenous vancomycin twice daily and intravenous acyclovir three times daily with a suspected but yet unknown infection.\nHe had negative serologies over the initial week for the following infections: streptococcus, syphilis, Ross River virus, Barmah Forest virus, alphavirus, Rickettsia rickettsii, measles, mumps, leptospirosis, parvovirus B19, enterovirus, varicella and HIV.\nHistological examination of biopsies revealed conflicting features. A biopsy of the hand showed evidence of spongiotic dermatitis with eosinophilic dermal infiltrates and occasional intra-epidermal vesicles harbouring Langerhans cells. A second specimen of the abdomen revealed acute neutrophilic suppurative folliculitis. Direct immunofluorescence of the abdomen biopsy was negative. These results were considered inconsistent with the clinical impression of AGEP held at that time. Further biopsies were then taken from his chest and left thigh, which showed spongiform subcorneal pustules accompanied by dermal inflammatory infiltrates and perivascular infiltrates with occasional eosinophils reported as ‘acute neutrophilic folliculitis’. Acanthosis and papillomatosis were not observed. A biopsy of the right foot favoured a spongiotic hypersensitivity reaction with a vasculitic component.\nClinically, his symptoms appeared to indicate AGEP at this stage, and given that serologies up until this point were negative, he was started on oral prednisone 0.5 mg/kg and topical betamethasone dipropionate 0.05% ointment twice daily, with a very good effect over the proceeding 5 days. It was only on day 6 of this treatment that, with the help of the infectious diseases team, a positive scrub typhus (Orientia tsutsugamushi) Igtotal serology was confirmed, with a titre of 1:128. This was not considered a primary infection, and paired tests 1 and 4 weeks later showed that the titre was stable and that this was likely an old rickettsial infection or a cross-reaction. This was also paired with scrub typhus and spotted fever PCR testing, which was also negative. Prednisone was weaned down to half the dose over the following 5 days, and he was discharged home on day 13 of admission (significantly improved on emollients and weaning dose of prednisone). Post-pustular desquamation was observed around this time. An outpatient review 12 days following discharge revealed a slight flare-up again at home after taking ibuprofen tablets for 48 h for aches and pain. However, this resolved promptly with the cessation of the non-steroidal anti-inflammatory drug.