Aspergilloma in a hydatid cavity

Abstract

Fungal colonization by aspergillus usually occurs in pre-existing lung cavities mostly due to post-tubercular sequelae. Colonization of a hydatid cavity is very rare. We hereby report this unusual co-infection in a 55 years old diabetic male patient who was diagnosed pre-operatively and was managed with surgery, anti-fungal agents, and anthelminthics. The possibility of this co-infection should make clinicians more vigilant in managing hydatid cysts in diabetics and immunocompromised, as they may have concomitant fungal infestation of the hydatid cavity.

Introduction

Hydatid disease is caused commonly by Echinococcus granulosus which mostly involves liver and lungs [1]. Human beings are an accidental host in the life cycle of the parasite. It results in the formation of a hydatid cyst in the lung with bronchial communication. Aspergillus is a saprophytic fungus which can infest pre-existing lung cavities, mostly post-tubercular (TB) [2]. It can also occur in cavities due to sarcoidosis, lung abscess, bronchiectasis, and cavitary malignancies. But, aspergillus colonization of a hydatid cavity is very rarely reported [3–5]. In previous large experiences of management of thoracic hydatid disease and aspergilloma reported from India, such an association was not seen [6, 7]. We hereby present a case with such an association.

Case report

This 55 years old farmer, who was a chronic smoker with 30 pack years and a recently diagnosed diabetic, presented with haemoptysis for 3 months. A computed tomogram (CT) was done which showed a well-defined lesion in the left lower lobe of the lung with mediastinal lymphadenopathy, which was highly suspicious of a malignancy (Fig. 1a, b). A CT-guided biopsy was done which showed aspergillosis and lamellated membranes suggestive of hydatid cyst. Fiber-optic bronchoscopy showed a normal bronchial tree with no abnormalities. The patient was started on voriconazole and albendazole and was referred for surgery. The chest was entered through a postero-lateral thoracotomy after lung isolation. The dense adhesions of the lower lobe with the diaphragm and the chest wall were released with difficulty. The thoracic cavity was packed with cetrimide-soaked sponges. The fissure was not well formed and was developed with difficulty. The lower lobe pulmonary arterial branches were ligated and divided followed by the inferior pulmonary vein. The lower lobe bronchus was divided using a stapler. The cavity was opened which showed hydatid membranes and blackish fungal material (Fig. 2a, b). It was sent for cultures and histopathology. Cultures grew septate fungal hyphae suggestive of aspergillus. The histopathology showed non-invasive aspergillosis (Fig. 3a, b) and hydatid disease (Fig. 3c, d).

Fig. 1.

a Computed tomography (CT) thorax lung window showing a well-defined subpleural low density nodular area of consolidation in the left lung lower lobe (yellow star). b Computed tomography (CT) thorax mediastinal window showing few borderline mediastinal and bilateral hilar lymph nodes (yellow arrow)

Fig. 2.

a Intra-operative photograph showing the resected lobe with the hydatid cyst opened, showing hydatid membranes (yellow star) and fungal ball (white star). b The hydatid membranes (black arrow) and the fungal ball (white star) are shown separately for better visualization

Fig. 3.

a Photomicrograph showing the septate fungal hyphae (black arrow) (40 ×). b Photomicrograph showing the septate fungal hyphae (black star) — periodic acid-Schiff stain (100 ×). c Photomicrograph showing the hydatid membrane (blue star) surrounded by a granuloma (40 ×). d Photomicrograph showing the lamellated hydatid membranes (blue star) and septate fungal hyphae (red star) in a same Sect. (40 ×)

Discussion

Aspergillus colonization usually occurs in pre-existing lung cavities. It is most commonly associated with TB in India [8]. The upper lobes are most commonly involved as TB mostly affects the upper lobes [6]. The lower lobes are commonly involved in cavities due to other aetiologies [6]. Colonization of a hydatid cavity occurs very rarely. The spores might reach the cavity through its bronchial communication. As the cavity is inaccessible to immune cells, these spores can grow freely inside the cavity. Hydatid of the lung more commonly affects the lower lobes [7]. This might be the reason that the aspergilloma was in the lower lobe in our patient. Diabetes is the most common associated co-morbidity in patients with aspergilloma [6]. Our patient was a recently diagnosed diabetic with a HbA1c of 9% showing that his glycaemic state was poorly controlled. This would have predisposed him to be infested by fungus. He was also a farmer exposed to animals like dogs which could explain how he contracted hydatid disease. The surgery recommended for aspergilloma is anatomical lung resection like segmentectomy or lobectomy, except for peripherally located simple aspergillomas which could be wedged out, while for a hydatid cyst, an excision and capitonnage would suffice. In our patient, as both the pathologies were diagnosed pre-operatively, he was planned for a left lower lobectomy. The surgery for aspergilloma is usually very difficult due to dense adhesions and dilated vascular chest wall collaterals [6]. Hence, an open left lower lobectomy was performed. The patient was continued on antifungals and anthelminthics which were started pre-operatively. The duration of anti-fungal therapy depends on the presence of angio- or tissue invasion. Anti-fungal therapy was stopped in our patient after the final surgical histopathology report suggested no evidence of invasion. In cases of invasive aspergillosis, voriconazole would be continued for 6 to 12 weeks depending on inflammatory parameters like C reactive protein [6]. He was also prescribed albendazole for 4 cycles of 1 month each with a gap of 2 weeks in between cycles and praziquantel, once a week for 6 weeks [7]. The incidence of aspergilloma in a hydatid cyst was reported as 2% in a retrospective pathological analysis of 100 hydatid cysts [9]. One systematic review showed that there were 22 cases of this rare co-infection reported between 2009 and 2014 [10]. In the management of hydatid, especially in the diabetics and immunocompromised, the possibility of fungal colonization has to be always thought out and looked for during surgery.

Conclusion

This co-infection of hydatid and aspergillus is indeed very rare. There should be a high index of suspicion of a fungal colonization in patients with hydatid cavities, especially in the immunocompromised and diabetics.

Author contribution

All authors contributed to the study conception and design. Material preparation and intra-operative photographs were taken by Raj Kumar Joel. The manuscript was written by Santhosh Regini Benjamin. The surgery was done by Vinay Murahari Rao. The histopathology and microbiology reporting were done by Twisha Adhikari and Lydia Jennifer. All authors read and approved the final manuscript.

Funding

None.

Declarations

Informed consent

Written consent for studies and publication was obtained from the patient prior to the procedure.

Conflict of interest

None of the authors declare any conflict of interest.

Human and animal rights

The study has been performed in accordance with the ethical standards as laid down in the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. This article does not contain any studies with animals performed by any of the authors.

IRB Approval

The approval of the Institutional Review Board was waived as it was a retrospective case study where the identity of the patient was not revealed.