Herpes simplex viral (HSV) pneumonia is a less commonly recognized cause of pneumonia in patients admitted to the Intensive Care Unit. We report a case of fatal herpes simplex pneumonia in a post thoractomy patient.
: A 67 year old woman with stage IIIa left upper lobe (LUL) squamous cell carcinoma received one cycle of neoadjuvant chemotherapy with Cisplatinum and Taxotere. The immediate post chemotherapy period was complicated by a brief episode of febrile neutropenia. She was empirically treated with broad spectrum antibiotics. Three months following neoadjuvant chemotherapy, she underwent left thoracotomy with LUL lobectomy and pericardial repair. On post operative day (POD) 3, she developed progressive hypoxemia, chest tightness and bilateral diffuse infiltrates. She was started on broad spectrum empiric antibiotic coverage with Cefepime, Vancomycin and Ciprofloxacin. On POD 4, the patient’s condition continued to worsen, and she required endotracheal intubation. Her sputum cultures were negative for bacteria and fungi. Clinically, there was no evidence of cardiogenic pulmonary edema. On POD 5, patient received stress dose steroids (Hydrocortisone 50 mg iv every six hours), which was tapered to off over next five days. On POD 6, the patient had episodes of high grade fever with worsening leucocytosis (20,000/dL) so Fluconazole had to be empirically added. Deep tracheal secretions were sent to culture, which turned out negative. The patient started improving slowly in the following days. However on POD 10, she again had episodes of high grade fever. After a sputum culture, Fluconazole and Cefepime were changed to Caspofungin and Meropenem respectively. No other sources of infections were identified. The patient also had worsening renal failure for which hemodialysis was initiated. A urine Legionella antigen was negative. Repeat sputum specimen was negative for bacteria or fungi. The patient’s A-a gradient continued to worsen and on POD 16 she required ventilatory support with airway pressure release ventilation. Her condition worsened further on POD 28, when she developed disseminated intravascular coagulation with upper gastrointestinal bleeding. On POD 31, the family decided to provide her comfort care and she was terminally extubated. A limited chest autopsy was performed. Sections of lung revealed diffuse necrotizing pneumonia. The respiratory epithelium and the alveoli were filled with atypical cells, which by immunohistochemisty were positive for HSV (both 1 and 2 types) infected cells. The cells demonstrated nuclear molding, multinucleation, and intranuclear inclusions. She also had herpetic esophagitis but no oral lesions were seen.
The exact role of HSV isolation in mechanically ventilated patients—whether it is a true pathogen leading to morbidity/mortality or an asymptomatic carrier remains a matter of debate. Current guidelines do not routinely recommend testing for herpes pneumonia. However, early diagnosis by bronchoscopy and bronchial washing, can be made by identifying HSV virus itself, immunohistochemistry or isolating specific herpetic nuclear inclusion bodies in bronchoalveolar lavage. If diagnosed early, HSV pneumonia may be successfully treated with Acyclovir. The major risk factor for HSV infection in our patient was immunocompromised status after chemotherapy. In addition, Camazine et al. have suggested that thoractomy in thoracic oncology patients by itself is a significant factor for immunosuppression. She probably had reactivation of HSV in the oropharynx. Pulmonary involvement may have resulted from local extension from the oropharynx after intubation and prolonged mechanical ventilation.
HSV pneumonia should be considered in an immunocompromised patient not responding to antibiotics and antifungal agents.
Ritwick Agrawal, No Financial Disclosure Information; No Product/Research Disclosure Information