Initial information received on 17-Jul-2018 regarding an unsolicited valid serious case issued from a literature article. This case involves a 37 years old male patient who experienced atypical pneumonia, worsening hypoxemic respiratory failure, possible connective tissue disease and rash, while he received vaccine DIPHTHERIA, TETANUS AND ACELLULAR PERTUSSIS VACCINE. The patient's past medical history, medical treatment(s), vaccination(s) and family history were not provided. On an unknown date, the patient received a dose of suspect DIPHTHERIA, TETANUS AND ACELLULAR PERTUSSIS VACCINE produced by unknown manufacturer lot number not reported. On an unknown date, the patient developed a serious myalgia fatigue, anorexia (decreased appetite) and rash, few days following the administration of DIPHTHERIA and TETANUS AND ACELLULAR PERTUSSIS VACCINE. The patient was hospitalized for these events. On an unknown date, the patient developed a serious dyspnea on exertion, worsening hypoxia, shortness of breath, weight loss and fever with the diagnosis of atypical pneumonia, worsening hypoxemic respiratory failure, possible connective tissue disease, Interstitial lung disease following the administration of DIPHTHERIA and TETANUS AND ACELLULAR PERTUSSIS VACCINE. The patient was hospitalized for these events. He was evaluated by his primary care physician and was told he had a typical post-immunization response. His symptoms progressed to fever, weight loss, and shortness of breath. He presented to the emergency department (ED) a month post vaccination and was treated for pneumonia with doxycycline for 10 days without significant improvement. A week later, he returned to the ED and was admitted for work up of possible Type 3 Hypersensitivity reaction to vaccine. His work up showed positive antinuclear antibody (ANA), SSA, and anti-RNP with elevated CK peaked at 701 U/L. CT chest at that time showed minimal basilar interstitial changes He was started on prednisone 80mg daily, and LEVAQUIN 500mg daily, supplemental oxygen, and discharged home with a diagnosis of Atypical pneumonia and possible connective tissue disease. After a week, he was admitted for worsening hypoxemic respiratory failure and a repeat CT of the chest revealed diffuse ground glass opacities consistent with pneumonitis. Despite treatment with high dose steroids and five days of IVIG, the patient's disease progressed. Due to lack of clinical response, he required venovenous extracorporeal (VV ECMO) support briefly. He underwent successful bilateral lung transplantation and was currently doing well. Relevant tests included positive ANA, SSA, and anti-RNP with elevated CK peaked at 701 U/L. CT chest at that time showed minimal basilar interstitial changes. Repeat CT of the chest revealed diffuse ground glass opacities consistent with pneumonitis. Pathology from native lung explants showed acute and organizing diffuse alveolar damage. Final diagnosis was rash, possible connective tissue disease, worsening hypoxemic respiratory failure and atypical pneumonia. The patient was treated with DOXYCYCLINE, PREDNISONE, LEVAQUIN and OXYGEN. On an unknown date, the patient was recovered from dyspnea on exertion and worsening hypoxia (duration reported as 1 month). The outcome of the other events was recovering/resolving. List of documents held by sender: none. Sender's Comments: Patient was diagnosed with Atypical pneumonia, Hypoxic respiratory failure and connective tissue associated interstitial lung disease after vaccination with DIPHTHERIA, TETANUS AND ACELLULAR PERTUSSIS VACCINE. Exact time to onset is unknown. Details regarding patient's medical history, immune status, other underlying conditions prior to vaccination as well as infectious work-up and information on infections occurring prior to vaccination are needed for complete assessment of the case. Based on the available information, no conclusion on the role of the vaccine can be drawn.