|LETTER TO EDITOR
|Year : 2019 | Volume
| Issue : 3 | Page : 273-274
Lung hydatid cyst, an immunological process, not a pearl formation
Beuy Joob1, Viroj Wiwanitkit2
1 Sanittion 1 Medical Academic Center, Bangkok, Thailand
2 Department of Biological Science, Joseph Ayobabalola University, Ikeji-Arakeji, Nigeria
|Date of Web Publication||24-Apr-2019|
Dr. Beuy Joob
Sanittion 1 Medical Academic Center, Bangkok
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Joob B, Wiwanitkit V. Lung hydatid cyst, an immunological process, not a pearl formation. Lung India 2019;36:273-4
We read with great interest the publication entitled, “'Pearl' in the lung: Hydatid membrane” by Baldi et al. Baldi et al. reported the case of a patient with lung hydatid cyst presenting with “a glistening pearly white membranous structure occluding the lumen of the right upper lobe anterior segment.” Baldi et al. mentioned for an interesting finding from bronchoscopy examination and proposed that “the mechanism of formation of hydatid cyst (hosts reaction to a parasite) is quite analogs to the formation of natural pearls, hence the title.” We agree that this is an interesting uncommon case of hydatid disease, a helminthic infestation. Nevertheless, the statement regarding the nature and development of white membranous structure is not correct. Regarding the hydatid cyst formation, the inflammation is the primary biological change, and the role of leukocyte in inflammatory response is detectable. Fibrosis is the common pathology of hydatid cyst in internal organ. This pathological process is totally different from that of pearl formation. For pearl formation, the basic process is the mineralization controlled by shell matrix gene. There is no immunological process or inflammatory response in pearl formation, but those phenomena are observable in hydatid cyst formation. Hence, there should be no analog to the formation of natural pearls in this patient. In the present case, the appearance of the white membranous structure might look like a pearl, but this picture should be due to the light effect which is a common phenomenon during performing flexible bronchoscopy examination. The light reflection might result in the whitish pearl-like appearance seen in the clinical picture in the report by Baldi et al.
Clinically, hydatid disease is an important uncommon parasite infection. The disease is sporadically reported from several countries, especially those in the tropical zone. The patient might present with nonspecific respiratory complaint. The chronic history is common. Due to the nature of silent parasitic infection, some cases might not have any clinical symptom. The diagnosis of lung hydatid cyst is usually by chance. Indeed, the diagnosis of lung hydatid cyst is usually difficult. The lung imaging usually shows a less mass. In the present case report, chest X-ray abnormality is also observed. The unexplained lung mass is a common first clinical presentation of lung hydatid cyst. The diagnosis of lung hydatid cyst is usually delayed. In general, the final diagnosis by fine-needle biopsy is usually not possible. At present, the recommended gold standard for diagnosis of lung hydatid cyst is combined video bronchoscopy and bronchoalveolar lavage fluid examination. Of interest, the clinical data in the present case report are extremely limited. In the present case report, the detail of final diagnosis is also not available. In additional, there is no histopathological figure. Nevertheless, the white membranous structure was not finally clarified for its nature. The treatment and outcome is also not mentioned.
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