A cluster of lung injury associated with home humidifier use: clinical, radiological and pathological description of a new syndrome.
BACKGROUND
Over a few months in the spring of 2011, a cluster of patients with severe respiratory distress were admitted to our intensive care unit (ICU). Household clustering was also observed. Extensive laboratory investigations failed to detect an infectious cause.


METHODS
Clinical, radiological and pathological investigations were conducted and the Korean Center for Disease Control performed epidemiological studies.


RESULTS
The case series consisted of 17 patients. Their median age was 35 (range 28-49) years. Six were pregnant at presentation and four had given birth 2 weeks previously. All presented with cough and dyspnoea. In the majority of patients (14/17), multifocal areas of patchy consolidation were identified in the lower lung zones on the initial CT. As the condition progressed, the patchy consolidation disappeared (10/13) and diffuse centrilobular ground-glass opacity nodules started to predominate and persist. Pathological specimens (11/17) showed a bronchiolocentric, temporally homogenous, acute lung injury pattern with sparing of the subpleural and peripheral alveolar areas. Ten patients required mechanical ventilation, eight of whom subsequently received extracorporeal life support. Four of the latter underwent lung transplantation. Five of the six patients in the ICU who did not receive lung transplantation died. An epidemiological investigation revealed that all patients had used humidifier disinfectants in their homes.


CONCLUSIONS
This case series report showed that lung injury and respiratory failure can occur as a result of inhaling humidifier disinfectants. This emphasises the need for more stringent safety regulations for potentially toxic inhalants that might be encountered in the home.
Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Sang-Bum
SB
Hong
Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Hwa Jung
HJ
Kim
Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Jin Won
JW
Huh
Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Kyung-Hyun
KH
Do
Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Se Jin
SJ
Jang
Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Joon Seon
JS
Song
Inhalation Toxicology Center, Korea Institute of Toxicology, Jeongeup, South Korea.
Seong-Jin
SJ
Choi
Inhalation Toxicology Center, Korea Institute of Toxicology, Jeongeup, South Korea.
Yongju
Y
Heo
Toxicologic Pathology Center, Korea Institute of Toxicology, Daejeon, South Korea.
Yong-Bum
YB
Kim
Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Chae-Man
CM
Lim
Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Eun Jin
EJ
Chae
Department of Nursing, Hanyang University, Seoul, South Korea.
Hanyi
H
Lee
Department of Nursing, Asan Medical Center, Seoul, South Korea.
Miran
M
Jung
Inhalation Toxicology Center, Korea Institute of Toxicology, Jeongeup, South Korea.
Kyuhong
K
Lee
Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Moo-Song
MS
Lee
Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Younsuck
Y
Koh
D000328:Adult; D016902:Air Pollution, Indoor / Q000009:adverse effects*; D003937:Diagnosis, Differential; D004196:Disease Outbreaks; D004202:Disinfectants / Q000633:toxicity*; D015199:Extracorporeal Membrane Oxygenation; D005260:Female; D006801:Humans; D006813:Humidity; D019570:Inhalation Exposure / Q000009:adverse effects*; D007362:Intensive Care Units; D055370:Lung Injury / Q000139:chemically induced* / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D016040:Lung Transplantation; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D011247:Pregnancy; D056910:Republic of Korea / Q000453:epidemiology; D012121:Respiration, Artificial; D013577:Syndrome; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D004202:Disinfectants
ARDS