Dual infection: Dengue fever with Legionella pneumonia complicated with acute kidney injury and rhabdomyolysis

Abstract

Background: Concurrent infection of dengue fever with legionella pneumonia is relatively rare occurrence as there is no case report documented in literatures. Treating dengue fever with bacterial infection has been an emerging challenge for physician. Legionella pneumophila is a common, usually underreported and undiagnosed cause of community acquired pneumonia which can lead to significant morbidity and mortality. We present a case of previously healthy man diagnosed as dengue fever with legionella pneumonia complicated with severe acute respiratory distress syndrome, acute renal failure and rhabdomyolysis. Case Description: A 42 y old gentleman with underlying bronchial asthma presented to emergency department with three days history of fever, nonproductive cough for two d with shortness of breath and chest discomfort. He was febrile, tachypneic and tachycardic. His blood pressure was 150/80 mmHg and saturating at 95% on room air. Crepitations were present on the right lower zone. Reviews of other system unremarkable. His full blood count showed leucopenia with thrombocytopenia. His Urea and creatinine were high. Creatine kinase was tremendously high reaches 34000 U/L indicates rhabdomyolysis. Arterial blood gas showed type 1 respiratory failure. Chest xray revealed consolidation over right basal with right sided pleural effusion. His rapid dengue serology noted NS1 antigen positive and dengue PCR revealed dengue genotype 1. He was placed on mechanical ventilation as respiratory distress worsened with hypoxemia. Empirically intravenous ceftriaxone was given to cover for pneumonia. However, he was rapidly deteriorated into septic shock. Subsequently noted that Legionella pneumophila Urinary Antigen was positive. Thus, azithromycin was prescribed. He has improved dramatically over the next 48 h and became hemodynamically stable. Discussion: Legionnaires disease was diagnosed as the cause of the clinical spectrum described. Acute kidney injury and rhabdomyolysis gradually improved after azithromycin commencement. In this case as the patient had dengue fever with legionella pneumonia, the cause for pleural effusion became a challenging part for physician. Treatment with appropriate fluid resuscitation, antibiotics and various modes of mechanical ventilation in the intensive care unit were successful. Conclusion: The presentation of progressively worsening respiratory distress or sepsis with dengue fever should raise the treating physician's suspicion of concurrent infection to reduce dengue fever associated mortality.