Pulmonary manifestations of ascariasis
- Peter F Weller, MD, FACP
Peter F Weller, MD, FACP
- Editor-in-Chief — Infectious Diseases
- Section Editor — Tropical Medicine
- William Bosworth Castle Professor of Medicine
- Harvard Medical School
- Professor of Immunology and Infectious Diseases
- Harvard T. H. Chan School of Public Health
- Karin Leder, MBBS, FRACP, PhD, MPH, DTMH
Karin Leder, MBBS, FRACP, PhD, MPH, DTMH
- Section Editor — Travel Medicine
- Head of Infectious Diseases Unit
- Monash University, Australia
Three types of helminths have life cycles in which infecting larvae reach the lungs via the bloodstream: Ascaris, hookworm, and Strongyloides . Two Ascaris species may elicit pulmonary symptoms in humans: Ascaris lumbricoides and Ascaris suum; these species are genetically very closely related and may be a single species [2-5].
The pulmonary manifestations of Ascaris infection are reviewed here. The epidemiology, clinical manifestations, and diagnosis of ascariasis are discussed separately, as are general issues related to pulmonary eosinophilia. (See "Ascariasis" and "Causes of pulmonary eosinophilia".)
Pulmonary ascariasis is rare in highly endemic areas with ongoing exposure [7,8]; it occurs most often in the setting of episodic exposure [9-11]. One study in Colombia (where intestinal Ascaris infection rates range from 25 to 90 percent) noted only four cases of Loeffler syndrome among about 13,000 subjects .
There is an increasing recognition that A. suum can cause human infection and symptomatic pulmonary ascariasis. Two reported cases of pulmonary ascariasis initially thought to be due to A. lumbricoides  were subsequently reconsidered by the authors to be due to A. suum [12,13]. Cases of pulmonary ascariasis have also been attributed to A. suum infection in Japan, China, Denmark, and the United States [2,14-16].
- Akuthota P, Weller PF. Eosinophilic pneumonias. Clin Microbiol Rev 2012; 25:649.
- Miller LA, Colby K, Manning SE, et al. Ascariasis in humans and pigs on small-scale farms, Maine, USA, 2010-2013. Emerg Infect Dis 2015; 21:332.
- Koino, S. Experimental infections on human body with ascarides. Jpn Med World 1922; 2:317.
- TAKATA I. Experimental infection of man with Ascaris of man and the pig. Kitasato Arch Exp Med 1951; 23:151.
- Phills JA, Harrold AJ, Whiteman GV, Perelmutter L. Pulmonary infiltrates, asthma and eosinophilia due to Ascaris suum infestation in man. N Engl J Med 1972; 286:965.
- Dold C, Holland CV. Ascaris and ascariasis. Microbes Infect 2011; 13:632.
- Spillmann RK. Pulmonary ascariasis in tropical communities. Am J Trop Med Hyg 1975; 24:791.
- Joob B, Wiwanitkit V. Loeffler's syndrome, pulmonary ascariasis, in Thailand, rare or under-reported? J Thorac Dis 2012; 4:339.
- LOFFLER W. Transient lung infiltrations with blood eosinophilia. Int Arch Allergy Appl Immunol 1956; 8:54.
- Gelpi AP, Mustafa A. Seasonal pneumonitis with eosinophilia. A study of larval ascariasis in Saudi Arabs. Am J Trop Med Hyg 1967; 16:646.
- Gelpi AP, Mustafa A. Ascaris pneumonia. Am J Med 1968; 44:377.
- Hoenigl M, Valentin T, Zollner-Schwetz I, et al. Pulmonary ascariasis: two cases in Austria and review of the literature. Wien Klin Wochenschr 2010; 122 Suppl 3:94.
- Hoenigl M, Seeber K, Valentin T, et al. Pulmonary ascariasis in patients from wealthy countries: shift in epidemiology? Int J Infect Dis 2012; 16:e888.
- Izumikawa K, Kohno Y, Izumikawa K, et al. Eosinophilic pneumonia due to visceral larva migrans possibly caused by Ascaris suum: a case report and review of recent literatures. Jpn J Infect Dis 2011; 64:428.
- Nejsum P, Parker ED Jr, Frydenberg J, et al. Ascariasis is a zoonosis in denmark. J Clin Microbiol 2005; 43:1142.
- Zhou C, Li M, Yuan K, et al. Pig Ascaris: an important source of human ascariasis in China. Infect Genet Evol 2012; 12:1172.
- Murrell KD, Eriksen L, Nansen P, et al. Ascaris suum: a revision of its early migratory path and implications for human ascariasis. J Parasitol 1997; 83:255.
- Piggott J, Hansbarger EA Jr, Neafie RC. Human ascariasis. Am J Clin Pathol 1970; 53:223.
- BEAVER PC, DANARAJ TJ. Pulmonary ascariasis resembling eosinophilic lung; autopsy report with description of larvae in the bronchioles. Am J Trop Med Hyg 1958; 7:100.
- PROFFITT RD, WALTON BC. Ascaris pneumonia in a two-year-old girl. Diagnosis by gastric aspirate. N Engl J Med 1962; 266:931.
- Buendía E, Zakzuk J, Mercado D, et al. The IgE response to Ascaris molecular components is associated with clinical indicators of asthma severity. World Allergy Organ J 2015; 8:8.
- Ahumada V, García E, Dennis R, et al. IgE responses to Ascaris and mite tropomyosins are risk factors for asthma. Clin Exp Allergy 2015; 45:1189.
- Palmer LJ, Celedón JC, Weiss ST, et al. Ascaris lumbricoides infection is associated with increased risk of childhood asthma and atopy in rural China. Am J Respir Crit Care Med 2002; 165:1489.
- Bean WJ. Recognition of ascariasis by routine chest or abdomen roentgenograms. Am J Roentgenol Rad Ther Nucl Med 1965; 94:379.
- Sakai S, Shida Y, Takahashi N, et al. Pulmonary lesions associated with visceral larva migrans due to Ascaris suum or Toxocara canis: imaging of six cases. AJR Am J Roentgenol 2006; 186:1697.
- Okada F, Ono A, Ando Y, et al. Pulmonary computed tomography findings of visceral larva migrans caused by Ascaris suum. J Comput Assist Tomogr 2007; 31:402.
- Weller PF, Bach DS, Austen KF. Biochemical characterization of human eosinophil Charcot-Leyden crystal protein (lysophospholipase). J Biol Chem 1984; 259:15100.