Tropical pulmonary eosinophilia: a comparative evaluation of plain chest radiography and computed tomography

An interesting case of pulmonary infiltrates with eosinophilia: out of sight out of mind

Tropical pulmonary eosinophilia should be considered in patients presenting with respiratory symptoms and hypereosinophilia, even in areas not endemic for filariasis. This awareness may prevent morbidity associated with its late or wrong diagnosis. https://bit.ly/3t8hHVc.

The New Status of Parasitic Diseases in the COVID-19 Pandemic-Risk Factors or Protective Agents?

It is possible that parasites may influence the course of COVID-19 infection, as either risk factors or protective agents; as such, the current coronavirus pandemic may affect the diagnosis and prevention of parasitic disease, and its elimination programs. The present review highlights the similarity between the symptoms of human parasitoses and those of COVID-19 and discuss their mutual influence. The study evaluated selected human parasitoses with similar symptoms to COVID-19 and examined their potential influence on SARS-CoV-2 virus invasion. The available data suggest that at least several human parasitoses could result in misdiagnosis of COVID-19. Some disorders, such as malaria, schistosomiasis and soil-transmitted helminths, can increase the risk of severe infection with COVID-19. It is also suggested that recovery from parasitic disease can enhance the immune system and protect from COVID-19 infection. In addition, the COVID-19 pandemic has affected parasitic disease elimination programs in endemic regions and influenced the number of diagnoses of human parasitoses.

The role of HRCT in Tropical Pulmonary Eosinophilia

PURPOSE

To determine the pattern of pulmonary involvement in clinically confirmed patients of tropical pulmonary eosinophilia (TPE).

METHOD

An observational study on 13 patients with clinically confirmed TPE was performed to determine the CT scan appearances.

RESULTS

The predominant CT scan finding is the presence widespread ill-defined bronchocentric nodules, which need to be differentiated from other conditions.

CONCLUSION

The pattern of lung involvement on a CT scan can give a clue to the diagnosis of TPE in the correct clinical context. Radiologists in tropical countries should have a high index of suspicion for this diagnosis when reading scans showing widespread ill-defined bronchocentric nodules.

A Review of Clinical and Imaging Findings in Eosinophilic Lung Diseases

OBJECTIVE

The purpose of this article is to review the clinical and imaging findings associated with eosinophilic lung diseases.

CONCLUSION

The spectrum of eosinophilic lung diseases comprises a diverse group of pulmonary disorders that have an association with tissue or peripheral eosinophilia. These diseases have varied clinical presentations and may be associated with several other abnormalities. Characteristic imaging findings are often detected with chest radiography, and CT best shows parenchymal abnormalities. The integration of clinical, radiologic, and pathologic findings facilitates diagnosis and directs appropriate treatment.

Parasitic Diseases of the Lung

Parasitic infection is a major healthcare problem that affects millions of the world’s population. Immigration and global warming have changed the natural distribution of parasitic diseases far removed from endemic areas. The respiratory system can be affected by a broad spectrum of helminthic and protozoal parasitic diseases. The diagnosis of parasitic infection of the respiratory system may be delayed due to myriad clinical and radiographic presentations of parasitic diseases which make the diagnosis of these entities challenging. Pulmonologists need to be familiar with the epidemiology, clinical presentation, pathophysiology, and bronchoscopic findings of parasitic lung diseases, in order to provide proper management in a timely fashion. This review provides a comprehensive view of both helminthic and protozoal parasitic diseases that affect the respiratory system, especially the central airways.

Parasitic pneumonia and lung involvement

Parasitic infestations demonstrated a decline in the past decade as a result of better hygiene practices and improved socioeconomic conditions. Nevertheless, global immigration, increased numbers of the immunocompromised people, international traveling, global warming, and rapid urbanization of the cities have increased the susceptibility of the world population to parasitic diseases. A number of new human parasites, such as Plasmodium knowlesi, in addition to many potential parasites, have urged the interest of scientific community. A broad spectrum of protozoal parasites frequently affects the respiratory system, particularly the lungs. The diagnosis of parasitic diseases of airway is challenging due to their wide varieties of clinical and roentgenographic presentations. So detailed interrogations of travel history to endemic areas are critical for clinicians or pulmonologists to manage this entity. The migrating adult worms can cause mechanical airway obstruction, while the larvae can cause airway inflammation. This paper provides a comprehensive review of both protozoal and helminthic infestations that affect the airway system, particularly the lungs, including clinical and roentgenographic presentations, diagnostic tests, and therapeutic approaches.

Tropical pulmonary eosinophilia: pathogenesis, diagnosis and management

PURPOSE OF REVIEW

Tropical pulmonary eosinophilia is predominantly seen in the tropical and subtropical regions of the world. It is being increasingly reported from other parts of world, however, due to increases in global travel and migration. This review focuses attention on recent developments.

RECENT FINDINGS

Tropical pulmonary eosinophilia is an occult form of human filariasis. The gamma-glutaryl transpeptidase found in the infective L3 stage larvae of Brugia malayi has been found to have similarities with the gamma-glutaryl transpeptidase present on the surface of human pulmonary epithelium. It has, therefore, been proposed that filarial gamma-glutaryl transpeptidase may play an important role in the pathogenesis of tropical eosinophilia. Airway hyperresponsiveness, manifesting as asthma-like syndrome, has been reported in tropical pulmonary eosinophilia and it has been suggested that interleukin-4 induces and interferon-gamma suppresses filarial-induced airway hyperresponsiveness. The intense eosinophilic alveolitis seen in acute tropical pulmonary eosinophilia is suppressed by 3 weeks of treatment with diethylcarbamazine citrate. A mild eosinophilic alveolitis along with radiological, physiological and hematological abnormalities, though with reduced intensity, persists in some patients however.

SUMMARY

A chronic mild interstitial lung disease has been found to persist in tropical pulmonary eosinophilia despite treatment.

Tropical pulmonary eosinophilia

Tropical pulmonary eosinophilia (TPE) usually affects people living in the tropics, especially those in Southeast Asia, India, and certain parts of China and Africa. However, owing to the rising frequency of world-wide travel and the migration between continents, this disease is increasingly seen in the West, where the diagnosis can be easily missed since it is rarely encountered and can mimic many other conditions. Cases of TPE have typically been reported to masquerade as acute or refractory bronchial asthma. TPE results from a hypersensitivity reaction to lymphatic filarial parasites found in endemic regions. There is evidence that it is more likely to occur in nonimmune individuals, ie, visitors to endemic regions, than in individuals of endemic populations who have developed immunity to filarial infections. Clinical features include paroxysmal cough, wheezing and dyspnea, and systemic manifestations such as fever and weight loss. A history of residence in a filarial endemic region and a finding of peripheral eosinophilia >3,000/mm3 should initiate a consideration of this disease. Other criteria for the diagnosis of TPE include absence of microfilariae in the blood, high titers of antifilarial antibodies, raised serum total IgE >1,000 U/mL, and a favorable response to the antifilarial, diethylcarbamazine, which is the recommended treatment. This disease, if left untreated or treated late, may lead to long-term sequelae of pulmonary fibrosis or chronic bronchitis with chronic respiratory failure. Herein lies the importance of early diagnosis and treatment of TPE.