Vaccination failure; Bordetella Pertussis; Respiratory distress; Hypoxia; Respiratory failure; Streptococcus Pneumoniae; sedation; Leukemoid reaction; This case was reported in a literature article and described the occurrence of vaccination failure in a 16-year-old female patient who received DTP (A or W not known) (DTP vaccine) for prophylaxis.  Concurrent medical conditions included pulmonary hypertension (mild (group 3 diagnosed 10 years ago by a right heart catheterization)) and scoliosis.   On an unknown date, the patient received DTP vaccine at an unknown dose. On an unknown date, unknown after receiving DTP vaccine, the patient experienced vaccination failure (serious criteria hospitalization and GSK medically significant), pertussis (serious criteria GSK medically significant), respiratory distress (serious criteria GSK medically significant), hypoxia (serious criteria GSK medically significant), respiratory failure (serious criteria GSK medically significant), streptococcal infection, sedation and leukemoid reaction. The patient was treated with ceftriaxone and azithromycin. On an unknown date, the outcome of the vaccination failure, pertussis, respiratory distress, hypoxia, respiratory failure, streptococcal infection, sedation and leukemoid reaction were unknown.   The reporter considered the vaccination failure, pertussis, respiratory distress, hypoxia, respiratory failure, streptococcal infection, sedation and leukemoid reaction to be related to DTP vaccine.  Additional details were provided as follows: This case was reported in a literature article and described the suspected vaccination failure in a 16-year-old female patient, who was vaccinated with unspecified diphtheria, tetanus, and pertussis vaccine (manufacturer unknown) for prophylaxis. The patient had past medical history of mild pulmonary hypertension (group 3 diagnosed 10 years ago by a right heart catheterization), and idiopathic adolescent scoliosis. No information on patient's family history or concomitant medication was provided. On an unspecified date, the patient received unspecified diphtheria, tetanus, and pertussis vaccine (administration route and site unspecified, dosage unknown; batch number not provided). The age of vaccination was not provided. On an unspecified date, an unknown period after the vaccination, the patient presented with clinical deterioration secondary to pertussis. The patient was initially admitted to undergo a posterior spinal fusion for scoliosis but was transferred to the pediatric service on the first post-operative day (POD) for progressive respiratory distress and hypoxia requiring oxygen. The patient did not have cough, congestion or chest pain. The initial chest x-ray was concerning for pulmonary edema versus pneumonia and the patient was started on ceftriaxone. Despite antibiotics her respiratory distress progressed and the patient was transferred to the intensive care unit. Initially the patient's white cell count (WBC) was 29000, C-reactive protein was 280 and early sputum culture grew Streptococcus Pneumoniae. Ultimately, the patient experienced respiratory failure requiring intubation and sedation. Leukemoid reaction was noted on day 4 of hospitalization with a WBC of 60000. Further infectious workup revealed Bordetella Pertussis. The patient was started on azithromycin. The patient improved clinically over the course of one week and was able to discharge home on 1L of oxygen via nasal cannula. This case has been considered as suspected vaccination failure being the time to onset and the full schedule was unknown. This case has been considered as serious due to suspected vaccination failure and hospitalization. The author commented, "This case illustrates the emergence of severe pertussis, even among vaccinated patients. Although malignant pertussis, the most severe form, is better identified and studied in infants, it is important to consider pertussis within the differential diagnosis in patients who present with respiratory failure and leukemoid reaction, regardless of age and vaccination status. We hope to educate through this case, the importance to consider bordetella pertussis, even among vaccinated individuals, when evaluating patients who present with severe respiratory distress or develop respiratory failure. Pertussis can be diagnosed in all spectrums of age, in all geographical locations, especially after the revision of vaccination schedule and formulation, especially in those patients with underlying immunodeficiency, pulmonary, or cardiac pathology to avoid lethal consequences. Bordetella Pertussis is known to cause severe symptoms with leukemoid reaction in infants." This article corresponding to this case is not available for regulatory submission due to copyright restriction.      Lab Comments: Lab test done on an unknown date. The initial chest x-ray was concerning for pulmonary edema versus pneumonia and the patient was started on ceftriaxone. Early sputum culture grew Streptococcus Pneumoniae.