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Afebrile Pneumonia Syndrome Differential Diagnoses

  • Author: Dagnachew (Dagne) Assefa, MD, FAAP, FCCP; Chief Editor: Michael R Bye, MD  more...
Updated: Oct 13, 2015

Diagnostic Considerations

Some organisms acquired perinatally may not cause illness until later in infancy, including Chlamydophila pneumoniae,Ureaplasma urealyticum,Mycoplasma hominis, cytomegalovirus, and Pneumocystis jiroveci. Infants infected with these organisms present between age 4-11 weeks with an afebrile pneumonia characterized by a staccato cough, tachypnea, and, occasionally, hypoxia.

Infants with bacterial pneumonia often are febrile, but those with viral pneumonia or pneumonia caused by atypical organisms may have a low-grade fever or may be afebrile. The child's caretakers may complain that the child is wheezing or has noisy breathing.

Differential Diagnoses

Contributor Information and Disclosures

Dagnachew (Dagne) Assefa, MD, FAAP, FCCP Pediatric Pulmonologist, Pediatric Lung Care, Bon Secours

Dagnachew (Dagne) Assefa, MD, FAAP, FCCP is a member of the following medical societies: American Academy of Pediatrics, American Academy of Sleep Medicine, American College of Chest Physicians, American Thoracic Society, European Respiratory Society

Disclosure: Nothing to disclose.

Specialty Editor Board

Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Nothing to disclose.

Chief Editor

Michael R Bye, MD Professor of Clinical Pediatrics, State University of New York at Buffalo School of Medicine; Attending Physician, Pediatric Pulmonary Division, Women's and Children's Hospital of Buffalo

Michael R Bye, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Chest Physicians, American Thoracic Society

Disclosure: Nothing to disclose.

Additional Contributors

Susanna A McColley, MD Professor of Pediatrics, Northwestern University, The Feinberg School of Medicine; Director of Cystic Fibrosis Center, Head, Division of Pulmonary Medicine, Children's Memorial Medical Center of Chicago

Susanna A McColley, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Chest Physicians, American Sleep Disorders Association, American Thoracic Society

Disclosure: Received honoraria from Genentech for speaking and teaching; Received honoraria from Genentech for consulting; Partner received consulting fee from Boston Scientific for consulting; Received honoraria from Gilead for speaking and teaching; Received consulting fee from Caremark for consulting; Received honoraria from Vertex Pharmaceuticals for speaking and teaching.


Heidi Connolly, MD Associate Professor of Pediatrics and Psychiatry, University of Rochester School of Medicine and Dentistry; Director, Pediatric Sleep Medicine Services, Strong Sleep Disorders Center

Heidi Connolly, MD is a member of the following medical societies: American Academy of Pediatrics, American Thoracic Society, and Society of Critical Care Medicine

Disclosure: Nothing to disclose.

Judith R Grisi, PA-C Physician Assistant, Monmouth Ocean Pulmonary Medicine, CentraState Medical Center

Disclosure: Nothing to disclose.

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