Skin reactions to drugs or infections can be very important. CASE REPORT: A 14-year-old boy developed fever, a diffuse pustular rash and a respiratory distress. Chest X-rays and serology were consistent with an acute Chlamydia pneumoniae infection. A skin biopsy revealed an acute generalized exanthematous pustulosis. CONCLUSION: Acute generalized exanthematous pustulosis (AGEP) is a disease manifested by a diffuse eruption of follicular sterile pustules. Most of the cases are drug induced, but they may be secondary to viral or bacterial infections. We report the first case of AGEP in a child with an acute C. pneumoniae infection.