A report describes a case of a 39-year-old plumber who described a 2-day history of nausea, vomiting, diarrhea, fever and exertional dyspnea. His medical history was uncomplicated including atopic dermatitis (eczema) and a generalized anxiety disorder (on escitalopram). He refused any recent contact with raw sewage, was a nonsmoker and had not used any intravenous drugs, and had not experienced any recent dental procedure.

Examination revealed him to be pyrexic (40.2°C), plethoric, tachycardic (100 bpm), normotensive and saturating normally. He was subjected to blood cultures and was provisionally diagnosed with viral gastroenteritis.

The next morning, 2 of 4 blood culture bottles showed positive reports of Gram-positive cocci, subsequently identified as methicillin-sensitive Staphylococcus aureus (MSSA). Subsequently, he was found obtunded, lying immobile and supine, with photophobia, neck stiffness and a positive Kernig sign. Neither focal neurological signs, nor papilledema on direct ophthalmoscopy was found. Auscultation of the precordium revealed a grade 3 pansystolic murmur in the region of the apex, with no palpable thrill. No cutaneous stigmata of embolic disease were found; however, multiple eczematous lesions on the face, trunk and limbs were present. The skin was dry, with areas of lichenification which were worse on the knees and elbows. He regularly applied moisturizer and 1% hydrocortisone acetate cream; however, on exacerbations it was managed with 2.5% hydrocortisone acetate prescribed by his general practitioner. He gave a history of atopic dermatitis since childhood but had experienced more frequent exacerbations over the preceding 2years, without noticing any exacerbating factors. He gave the history of atopic dermatitis in two of his siblings as well as his two children. He never visited a dermatologist.

He was again subjected to blood cultures examination and was administered empirical doses of gentamicin, benzylpenicillin and vancomycin. After susceptibility testing and on infectious diseases specialist advice, the regimen was switched to flucloxacillin 2 g 6-hourly, and subsequently increased to 4-hourly.

Lumbar puncture was conducted to rule out bacterial meningitis, which revealed no red cells, no white cells, normal glucose, mildly raised protein (0.57 g/L), and no growth on aerobic and anaerobic culture, and negative polymerase chain reaction for Neisseria meningitidis, Herpes simplex, and Streptococcus pneumoniae.

Transthoracic echocardiogram revealed small vegetation on the posterior leaflet of the mitral valve, which had prolapsed, with moderate associated mitral regurgitation; which was reconfirmed along with revealing a widely patent foramen ovale.

A diagnosis of MSSA mitral valve endocarditis (Duke criteria diagnostic with 2 major, 1 minor) was made. All presenting symptoms and signs diminished within 48-hour of initiating therapy, and within 72-hour blood cultures evolved negative. 

It was concluded that the point of entry of MSSA was any one of the patients eczematous lesions which he had scratched to the point of hemorrhage.

He was prescribed a 6-week course of flucloxacillin 12 g continuous infusion daily. After the full course of antibiotic therapy, he underwent elective mitral valve repair and closure of the patent foramen ovale.

Source: Micallef MJ, Ramphul A. Infective endocarditis in a patient with atopic dermatitis. J Cardiol Cases. 2016;13(5):153-4.