Paragonimus westermani infection mimicking recurrent lung cancer: A case report

An unusual presentation of pulmonary nodules

A pulmonary nodule is a common radiological finding encountered in routine medical practice. It needs to be extensively evaluated as the differential diagnosis can range from sinister malignancies to fully treatable infectious causes. Here, we present a rare case of pulmonary paragonimiasis presenting as pulmonary nodule. This case report aims to sensitise the medical practitioner regarding pulmonary paragonimiasis which is completely treatable but carries a high risk of being under diagnosed.

The first case report of Paragonimus westermani infection diagnosed by transbronchial lung cryobiopsy

We report a case of pulmonary paragonimiasis diagnosed by transbronchial lung cryobiopsy (TBLC). TBLC is likely to be a superior method to transbronchial forceps biopsy because TBLC can get larger specimens, resulting in a higher chance of containing the eggs. A male patient aged 57 years presented with hemoptysis and dyspnea on exertion. His initial chest computed tomography scans showed a cavitary nodule with a peripheral ground-glass appearance, leading to a prescription of an oral antibiotic, with an initial assumption of pneumonia. A follow-up chest computed tomography, however, revealed an appearance of a new nodule adjacent to the original nodule. TBLC and transbronchial forceps biopsy were done to rule out lung cancer and eventually, the eggs of Paragonimus westermani were found using TBLC. Praziquantel was prescribed, showing improvements in symptoms and chest X-ray findings. TBLC has more potential to be utilized as a diagnostic method than transbronchial forceps biopsy because it has a better chance to confirm pulmonary paragonimiasis, which can be initially suspected as pulmonary tuberculosis or lung cancer.

The role of helminths in the development of non-communicable diseases

Non-communicable diseases (NCDs) like cardiovascular disease, chronic respiratory diseases, cancers, diabetes, and neuropsychiatric diseases cause significant global morbidity and mortality which disproportionately affect those living in low resource regions including low- and middle-income countries (LMICs). In order to reduce NCD morbidity and mortality in LMIC it is imperative to understand risk factors associated with the development of NCDs. Certain infections are known risk factors for many NCDs. Several parasitic helminth infections, which occur most commonly in LMICs, have been identified as potential drivers of NCDs in parasite-endemic regions. Though understudied, the impact of helminth infections on the development of NCDs is likely related to helminth-specific factors, including species, developmental stage and disease burden. Mechanical and chemical damage induced by the helminth in combination with pathologic host immune responses contribute to the long-term inflammation that increases risk for NCD development. Robust studies from animal models and human clinical trials are needed to understand the immunologic mechanisms of helminth-induced NCDs. Understanding the complex connection between helminths and NCDs will aid in targeted public health programs to reduce helminth-induced NCDs and reduce the high rates of morbidity that affects millions of people living in parasite-endemic, LMICs globally.

One delayed diagnosis of paragonimiasis case and literature review

Human paragonimiasis has been appearing all over the world due to increased human migration, international travel, and worldwide food trading. However, delayed and missed diagnosis rates are also increasing due to atypical clinical manifestations and the lack of disease understanding by clinical workers. We describe the case of a 43-year-old man, who was hospitalized with cough and chest pain for two months. Chest computed tomography (CT) revealed bilateral emphysema, left pleural effusion, and bilateral atelectasis. The hypereosinophilia gave us a clue; ultimately, the diagnosis of paragonimiasis was made through a diet history and a positive result of serum Paragonimus sp. immunoglobulin (Ig) G antibody. Moreover, 27 misdiagnosed paragonimiasis cases in the past decade have been reported. We draw conclusions by summarizing their characteristics for suspicious eosinophilic paragonimiasis patients; we should inquire diet history carefully, test serum IgG antibodies, and try to detect eggs. Once diagnosed, praziquantel is preferred for treatment.

[Pulmonary larval paragonimiasis mimicking lung cancer]

Larval paragonimiasis is a parasitic disease caused by lung fluke larvae. Unlike the classic form of paragonimiasis, the larval form occurs with a large number of clinical manifestations. However, this fact only complicates the diagnosis of larval paragonimiasis, for the abundance of clinical manifestations results in the misdiagnosis of other diseases. Another feature of this form of paragonimiasis is the tendency to generalize and mimic the clinical presentation of malignant neoplasms. The performed diagnostic measures failed to give an accurate view of the nature of the disease, therefore diagnostic thoracoscopy was carried out and biopsy specimens were taken from the subpleural region of dissemination, followed by urgent histologic examination suggestive of glandular cancer. This circumstance became the reason for atypical resection of the affected portion, which was done; however, the patient died from pulmonary thromboembolism on postoperative day 2. The main diagnosis of chronic pulmonary generalized paragonimiasis (cystic and pneumosclerotic phases) with neoplastic syndrome was posthumously made.

Paragonimus westermani infection manifesting as a pulmonary cavity and adrenal gland mass: A case report

We report a case of Paragonimus westermani infection simultaneously affecting two separate organs that presented as both a pulmonary cavity and adrenal mass in an immunocompromised host. A 65-year-old male with a previous kidney transplant visited our clinic because of hemoptysis. Chest computed tomography (CT) showed a pulmonary cavity and right adrenal gland mass. The Aspergillus antigen titer in bronchial lavage fluid was elevated and showed positive conversion. It was necessary to differentiate lung cancer with adrenal gland metastasis from a fungal infection with an adrenal gland adenoma. Positron emission tomography CT suggested benign disease, and it was misdiagnosed as pulmonary aspergillosis based on the elevated Aspergillus antigen titer in the bronchial lavage fluid. Owing to the adverse effects of anti-fungal treatment, the patient underwent wedge resection of the lung and P. westermani was confirmed. A careful history revealed that the patient had eaten raw freshwater crabs 3 years earlier, and a test for serum antibodies to P. westermani was positive. Despite treatment with praziquantel, the adrenal mass persisted on 3-month follow-up CT. A right adrenalectomy was performed and a P. westermani infection was confirmed.