Cutaneous manifestations of Crimean-Congo haemorrhagic fever: morbilliform eruptions may reflect a favorable outcome and not low platelet levels

ARTICLE

Auteur(s) : Melih AKYOL¹, Sedat ÖZÇELIK¹, Aynur ENGIN², Sibel Berksoy HAYTA¹, Fatma BIÇICI¹

¹Dermatology Department, Cumhuriyet University, School of Medicine, 58140 Sivas, Turkey
²Clinical Microbiology Department, Cumhuriyet University, School of Medicine, 58140 Sivas, Turkey

Crimean-Congo Haemorrhagic Fever (CCHF) is a zoonotic viral disease that is asymptomatic in infected animals. This virus is a member of the genus Nairovirus in the family Bunyaviridae. CCHF is widespread in Africa, the Middle East and Asia. CCHF has increased in the last five years in Turkey and it is emerging as a public health problem [1, 2]. The aim of this study was to reveal viral morbilliform eruptions and other cutaneous manifestations of CCHF.

The study group consisted of 35 patients who presented at the hospital between June and July 2009. Acute and convalescent phase serum samples were sent to the Virology Laboratory of Refik Saydam Hygiene Central Institute, Ankara, Turkey for serologic and virologic analyses. The definitive diagnosis of CCHF infection was based upon typical clinical and epidemiological findings and detection of CCHF virus-specific IgM by ELISA, or of genomic segments of the CCHF virus by reverse transcription-polymerase chain reaction (RT-PCR), in either the acute or convalescent phase of the disease. The patients were examined by two experienced dermatologists and the cutaneous manifestations were noted.

Laboratory analyses, including complete blood count, platelet count, liver function tests, urine analysis, prothrombin time (PT), activated partial thromboplastin time (aPTT) were evaluated in all patients. Seventeen patients received ribavirin treatment. All the patients in our study recovered without complications.

The mean age of the patients was 55.05 (range = 16-88, SD = 18.2). There were 26 (74.3%) males and 9 (25.7%) females. Twenty six (74.3%) patients had a history of a tick bite or contact. Bite marks could not be found in eight patients. Twenty nine patients (82.9%) lived in rural areas whereas 6 (17.1%) were in cities.

In our study, of the 35 patients with CCHF, 30 (83.3%) had associated mucocutaneous manifestations (table 1). Five patients (14.3%) had pruritus. The lips of five patients (14.3%) showed hemorrhagic crusting. Two patients (5.7%) had erythematous and crusting tongues.
Table 1 Mucocutaneous lesions and proportional distribution

The anatomical regions in which the lesions were most frequently seen were: upper extremities (62.9%), lower extremities (34.3%), posterior trunk (28.6%), head-neck (28.6%) and anterior trunk (25.7%).

The mean disease duration was 5.85 ± 2.78 days at the time of examination. All the patients had a thrombocytopenia. The mean value of platelet counts was 49,057.14 per mm³ (min-max: 6,000-98,000). Patients were divided into two groups according to the number of platelets. Morbilliform eruption was more frequently seen in patients with less than 50,000 platelets per mm³ of blood (p = 0.03, χ² = 4.29; Fisher exact test). Pearson correlation analysis was used to determine the relation between platelet count and having morbilliform eruption. A statistically significant moderate correlation between both parameters was found (p = 0.01, r = – 0.41). There was no relation between the morbilliform eruption and the use of ribavirin (p = 0.33, χ² = 0.93; Fisher exact test).

The most common skin findings of CCHF were petechia, purpura, and ecchimosis, consistent with the pathogenesis of the disorder. The anatomical regions where the lesions are mostly seen are the extremities, which are more liable to trauma. In two patients showing generalized lesions, platelet counts were 35,000 per mm³ and 28,000 per mm³.

Erythematous and petechial eruptions may be seen in patients with CCHF. Simple exanthems are erythematous changes in the skin without evidence of blistering or pustulation in typical morbilliform eruptions. The eruption typically starts on the trunk and spreads peripherally in a symmetrical manner, and may be maintained locally or become generalized. The most frequent differential diagnosis in these patients is drug eruption [3]. Morbilliform eruption was not significantly more frequently seen in our patients with ribavirin treatment. Therefore, in our study, morbilliform eruption, which was detected more frequently in patients with low platelet counts (< 50,000 per mm³), may be considered as a viral toxidermic reaction. Platelet count was below 20,000 per mm³ in only one of eleven patients with a morbilliform eruption in our study. Platelet count below 20,000 per mm³ is a prognostic factor in terms of fatal outcome according to Swanepoel criteria [4]. Consequently, morbilliform eruptions should be considered as viral toxidermic reactions rather than being a predictive factor for fatal outcome during the course of the disease.

CCHF is a viral disease causing mostly non-specific cutaneous manifestations, including petecchia/purpura, and ecchimosis. However, it should be kept in mind that morbilliform eruptions may be a sign of a reduced number of platelets in cases of CCHF.

Acknowledgements

References

2 Gunes T, Engin A, Poyraz O, et al. Crimean-Congo hemorrhagic fever virus in high-risk population, Turkey. Emerg Infect Dis 2009; 15: 461-4.

3 Shear NH, Knowles SR, Shapiro L. Cutaneous reactions to drugs. In: Wolff K, Goldsmith LA, Katz SI, et al., eds. Fitzpatrick's Dermatology in General Medicine. New York: McGraw Hill, 2008: 355-62.

4 Swanopoel R, Gill DE, Shepherd AJ, Leman PA, Mynhardt JH, Harvey S. The clinical pathology of Crimmean-Congo Haemorrhagic fever. Rev Infect Dis 1989; 11: 794-800.