Suspicion of monkeypox infection confirmed

Patients with exanthema accompanied by nonspecific fever should also be considered for monkeypox infection. Especially in case of monomorphic change of skin florescences, re-diagnosis is advisable. Vaccination should be considered for appropriate risk groups.

The route of monkeypox transmission is through close physical contact, most likely in the form of smear or droplet infection [1]. The incubation period is around 5 to 21 days. Typically, lymph node swelling, the appearance of an exanthema, and other specific skin lesions occur in the course [1]. The course is often self-limiting. Infectivity is consistent with symptom onset, so close contacts need not be isolated while patients are asymptomatic [2]. After all crusts have fallen off, patients are no longer considered infectious [3]. Histological and laboratory diagnostic examinations (e.g., electron microscopy) should be performed if a clinical diagnosis is suspected. WHO recommends confirmation of the diagnosis by PCR from the lesions [2].

Monkeypox has been known since 1958, and the first human infection was confirmed in Congo in 1970. Since then, the spread of the pathogen has been endemic in Central and West Africa, and isolated cases have occurred in the Western Hemisphere in connection with trade in exotic animals or international travel. Carriers of Orthopox virus are animal hosts (especially rats, squirrels, mice). Genetically distinct West African and Central African variants are known to have different virulences. PCR studies and sequencing in specialized laboratories can differentiate corresponding variants.

to [1,3,5,8–11]

Treatment of monkeypox infection is symptom-based. In highly symptomatic courses, therapy attempts with Tecovirimat and Brincidofovir are possible [4]. Severe complications are rare and occur mainly in patients who have not been vaccinated against smallpox [5]. Rare complications reported in the literature include bronchopneumonia, vomiting and diarrhea with severe dehydration, encephalitis, and sepsis [6].

Patient with fever, chills and pruritic exanthema

A 31-year-old male patient presented to the emergency department with fever, chills, and pruritic exanthema that had been present for 5 days [1]. Moreover, painful perianal skin lesions already occurred ten days ago after unprotected sexual contact (MSM). The patient reported changing sexual partners and HIV pre-exposure prophylaxis with emtricitabine and tenofovir. At initial presentation, there was a truncal maculopapular exanthema, sometimes with confluent efflorescences, and multiple perianal nodules with erosions, crusts, and necrosis. Inflammatory parameters were mildly elevated, and HIV serology findings were negative. Luesserology revealed a seroscar with no evidence of fresh infection in the condition after treated lues infection. PCR examination did not detect herpes simplex infection (HSV 1 and 2).

Histologic analysis of a punch biopsy from the abdomen revealed superficial perivascular lymphocytic dermatitis. Based on the initial suspected diagnosis of infection-triggered erythema exsudativum multiforme associated with perianal herpes simplex infection, systemic therapy with prednisolone (0.5 mg/kgKG) was initiated for three days, resulting in rapid healing of the exanthema. However, on the day of weaning, single standing pustules with erythematous margins appeared on the entire integument, accompanied by painful cervical lymph node swelling, dysphagia, and oral erosions.

The clinical courses of monkeypox infection vary widely, ranging from monosymptomatic to disseminated courses. The most common clinical symptoms are fever (54%), exanthema (40%), lymph node swelling (46%), headache (26%), fatigue (23%), and myalgias (17%). Newly described clinical manifestations include penile edema and rectal pain. In addition, genital and anal lesions (erosions and vesicles) occur during the course and pustules occur during the course; the pustules are morphologically similar to smallpox but often have an erythematous rim and may become erosive or necrotic. The skin symptoms are accompanied by itching and pain and heal with scarring. The first efflorescences typically occur at the site of exposure.

to [1,2,4,9,12,13]

PCR, biospy and electron microscopy for diagnostic confirmation

PCR examination of the pustule contents confirmed the suspected diagnosis of monkeypox infection [1]. A punch biopsy of a pustule on the left elbow was performed again. This revealed a central ulceration with hemorrhagic crust. Isolated viral inclusion bodies and an interface reaction with dense subepidermal lymphohistiocytic infiltrates were detected in the marginal area of the ulcer. In electron microscopic examination, cuboidal orthopox viruses with mulberry-like surface configuration could be observed. This finding is consistent with monkeypox. The patient was isolated and required to remain in home quarantine for a total of 21 days after discharge from the hospital. Perianal erosions continued to occur with heavy weeping. A proctoscopic examination revealed marked erosive proctitis with fibrinous plaques. Symptomatic therapy with Jelliproct and xylocaine gel was then initiated.

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