Problems with diagnostic criteria for humidifier disinfectant lung injury (HDLI): two cases of radiologically improved HDLI

Abstract

Background: In Korea, to investigate the casual relationship between humidifier disinfectant and lung disease, four rounds of investigation and judgment were conducted. During this investigation, two adults who performed lung biopsy were recognized for their relevance between humidifier disinfectants and lung disease. At first, we did not think of the relationship to humidifier disinfectant because chest computed tomography (CT) finding of 2 cases were improved. However, they performed lung biopsy and it showed typical humidifier disinfectant lung injury (HDLI) pathologic findings, they could be recognized as HDLI. We report these cases here. Case presentation: We selected 2 cases from the fourth-round investigation at Kangbuk Samsung Hospital. Patient of case 1 used humidifier disinfectants since September 2010. The patient was admitted 6 months later to the intensive care unit (ICU) due to severe dyspnea. Pathology following a lung biopsy revealed typical HDLI finding which was determined to be due to humidifier disinfectant exposure. Patient of case 2 used humidifier disinfectant from 2001 to 2008 for about 3 months each winter. The patient's cough and sputum production symptoms began in December of 2007. The patient was admitted to the respiratory medicine department due to worsening dyspnea. Pathology following a lung biopsy revealed typical HDLI finding. This was determined to have been caused by humidifier disinfectant exposure. Conclusions: Because the typical radiologic findings associated with HDLI can improve over time, it is necessary to consider the revision of current diagnostic criteria that the presence of radiologic findings is important.

Health Effects Associated With Humidifier Disinfectant Use: A Systematic Review for Exploration

“…For group 1, studies published on humans, a total of 49 articles were selected ( Table 2 ). 1 2 3 4 5 6 7 9 10 11 12 13 14 17 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 The suspicion that humidifier disinfectant might be a cause of lung damage was suggested in 2011. Studies in international journals began to appear in 2013.…”

“…Forty-eight published studies using non-human animal subjects or in vitro toxicology studies were included in the review ( Table 3 ). 16 39 40 41 42 43 44 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 To investigate the hazardous effects of humidifier disinfectants, in vitro studies were performed using various cell lines, and toxicity tests were performed using several animal models. Cytotoxicity, lung fibrosis, and pulmonary genotoxicity due to PHMG exposure were described as a consequence of toxicity testing undertaken shortly after HDLI was reported.…”

“…They were assumed to be observable in subsequent computed tomography findings. However, Nam et al 43 reported examples of the full elimination of the lesions in subsequent imaging following HDLI. The long-term follow-up of HDLI patients revealed that central lobular nodules remained in the majority of adults but disappeared in the majority of children.…”

A comprehensive study of deaths due to exposure to humidifier disinfectant in Korea: focusing on medical records, assessment of exposure to humidifier disinfectants, and causes of death

“…In summary, many applicants for death damage caused by humidifier disinfectants have not been recognized, and the complexity and various issues of damage determination are piling up. Hence, further efforts should be made to appropriately remedy the applicants for damage and continue the conduct of related studies and discussions [ 11 , 12 ]. In particular, the specific characteristics of the applicants for death damage caused by humidifier disinfectants and limitations of remedy for damage should be considered.…”