How to Differentiate Between Infantile Exanthem and Heat Rash

The following are the key differences between roseola infantum (sixth disease) and miliaria (heat rash): 1. **Different causes**: Roseola infantum is mainly caused by viral infections such as human herpesvirus 6 (HHV-6) and human herpesvirus 7 (HHV-7); whereas miliaria results from blocked sweat ducts due to failure of sweat to evaporate in hot and humid environments, leading to leakage of sweat into surrounding tissues. 2. **Differences in clinical manifestations**: Roseola infantum typically presents with sudden high fever lasting 3–5 days, followed by a rapid drop in temperature and the subsequent appearance of rose-colored macules or maculopapular rash. The rash usually begins on the trunk and spreads to the face, neck, and proximal limbs, without significant pruritus. In contrast, miliaria presents with densely distributed small papules, vesicles, or pustules accompanied by itching and a burning sensation, commonly occurring on the forehead, neck, chest, and back. 3. **Different treatment approaches**: Roseola infantum is primarily managed with symptomatic and supportive care, including the use of antipyretics for high fever. Miliaria requires maintaining skin cleanliness and dryness, using calamine lotion for itching relief, and considering topical glucocorticoids for severe symptoms. If you are unable to distinguish between the two conditions, it is recommended to seek timely medical advice from a healthcare professional.