Unmasking the chik sign: A case report on nasal hyperpigmentation as a diagnostic clue for chikungunya fever

Macular hyperpigmentation of the nasal region, often referred to as the ‘chik sign’, constitutes a distinctive physical manifestation associated with chikungunya fever. Chikungunya, a mosquitoborne viral illness, presents with acute febrile symptoms, intense arthralgia and cutaneous eruptions. The chik sign serves as a valuable clinical marker for discerning chikungunya from other febrile illnesses with analogous presentations, such as dengue fever and malaria. This differentiation is particularly crucial in endemic regions. Recognition of the chik sign underscores the significance of clinical acumen in diagnosing chikungunya. In conjunction with confirmatory laboratory testing, identification of this sign can augment diagnostic accuracy and guide appropriate therapeutic strategies. Herein, we present the case of a 44-year-old woman with chikungunya virus infection who exhibited acute febrile symptoms, severe polyarthralgia and hyperpigmentation of the nasal region. In conclusion, the chik sign is a crucial clinical marker for identifying chikungunya fever. Its identification can improve diagnostic precision and enable timely care, particularly in places with limited access to laboratory testing. Healthcare professionals should thus be vigilant for this skin pigmentation in patients who exhibit joint pain and feverish symptoms that are indicative of chikungunya virus infection. To further understand the clinical spectrum of chikungunya, more research into the presentation of this pigmentation would be helpful.