Background Hyperthermia is one of the most frequent causes of a child presentation to the paediatrician. Children with know chronic pneumopathies are likely to develop acute infectious exacerbations, like others. The aim paper presents the case of 9 years old boy with cystic fibrosis with hemoptysis and hyperthermia in the New Years Eve.

Methods Patient was diagnosed with cystic fibrosis in infancy with f 508 del homozygous genotype and is known with Staphylococcus aureus chronic pulmonary infection. He was on chronic ciprofloxacin treatment and started to have fever.

Results The initial supposition was a new exacerbation with Staphyloccocus or a new emergent pathogen, like Pseudomonas. Therefore he was admitted in the cystic fibrosis department and started the i.v. treatment with meropenem; unfortunately he continued to have fever and investigations revealed a minor inflammatory syndrome. Sputum samples were taken and during the evolution he continues to be febrile and developed mucosal candidiasis. Afyer 4 days of meronem, we constated the presence of granular lesions around Stenon canal, the IgM for measles was detected positive and exanthema appeared after 7 days.

Conclusion Not every fever or hemoptysis in a child with cystic fibrosis signifies an exacerbation. During a viral epidemic wave we have to think of child exposure risk, especially in patients with chronic pathologies.