Hot tub lung
Hot tub lung refers to pulmonary disease in otherwise healthy patients that can occur by secondary exposure to aerosolized non-tuberculous mycobacteria in contaminated hot water-steam (classically described in hot tubs, hence the name).
It can present as an acute pulmonary illness with fever and dyspnoea.
The pathology of hot tub lung is thought to be related to an infection, a hypersensitivity reaction (the latter is more favoured) or both. Therefore it is also sometimes classified as a precipitant for hypersentivity pneumonitis. A granulomatous pneumonitis then tends to occur.
Hypersensitivity pneumonitis-like reaction to mycobacteria can also occur from exposures other than just hot tubs.
Imaging appearances can mimic a subacute hypersensitivity pneumonitis from other causes 1. Described features include 1,5:
- areas of ground glass attenuation
- centrilobular pulmonary nodules
- air trapping on expiratory images
- beading of the interlobular septae
Interstitial lung disease
interstitial lung disease
- drug-induced interstitial lung disease
- hypersensitivity pneumonitis
idiopathic interstitial pneumonia (mnemonic)
- acute interstitial pneumonia (AIP)
- cryptogenic organising pneumonia (COP)
- desquamative interstitial pneumonia (DIP)
- idiopathic nonspecific interstitial pneumonia (NSIP)
- idiopathic pleuroparenchymal fibroelastosis
- lymphoid interstitial pneumonia (LIP)
- respiratory bronchiolitis–associated interstitial lung disease (RB-ILD)
- usual interstitial pneumonia / idiopathic pulmonary fibrosis (UIP/IPF)
- 1. Pham RV, Vydareny KH, Gal AA. High-resolution computed tomography appearance of pulmonary Mycobacterium avium complex infection after exposure to hot tub: case of hot-tub lung. J Thorac Imaging. 2003;18 (1): 48-52. Pubmed citation
- 2. Verma G, Jamieson F, Chedore P et-al. Hot tub lung mimicking classic acute and chronic hypersensitivity pneumonitis: two case reports. Can. Respir. J. 2008;14 (6): 354-6. Free text at pubmed - Pubmed citation
- 3. Hanak V, Kalra S, Aksamit TR et-al. Hot tub lung: presenting features and clinical course of 21 patients. Respir Med. 2006;100 (4): 610-5. doi:10.1016/j.rmed.2005.08.005 - Pubmed citation
- 4. Marchetti N, Criner K, Criner GJ. Characterization of functional, radiologic and lung function recovery post-treatment of hot tub lung. A case report and review of the literature. Lung. 2004;182 (5): 271-7. doi:10.1007/s00408-004-2508-1 - Pubmed citation
- 5. Hartman TE, Jensen E, Tazelaar HD et-al. CT findings of granulomatous pneumonitis secondary to Mycobacterium avium-intracellulare inhalation: "hot tub lung". AJR Am J Roentgenol. 2007;188 (4): 1050-3. doi:10.2214/AJR.06.0546 - Pubmed citation