Invasive aspergillosis of pulmonary hydatid cyst

Ann Saudi Med 29(1) January-February 2009 www.saudiannals.net 53 Pulmonary aspergillosis frequently complicates existing pulmonary cavity, which is commonly due to tuberculosis.1-6 Pulmonary aspergillosis has also been reported, though rarely, in pulmonary cavities as a consequence of the removal of a hydatid cyst.7-9 We report a case with active pulmonary hydatid disease that was co-infected with aspergillosis.

A 50-year-old male diabetic was diagnosed and treated for pulmonary tuberculosis 13 years ago. He presented with a 6-month history of low-grade fever and sweat-ing. He also had frequent hemoptysis for the previous 3 months. He was investigated at his local hospital and referred to us for management of pulmonary aspergil-loma. Examination was significant for low-grade fever and bronchial breath sounds with coarse crepitations in the right infrascapular region. A sputum smear was negative for acid-fast bacilli and grew Aspergillus. A plain chest x-ray showed a thick wall cavity in the up-per and mid zone adjacent to the right hilum. A highresolution CT scan revealed a large cavity in the apical segment of the right lower lobe with extensive lamellar internal echoes (Figure 1). Ultrasound of the abdomen revealed a simple hepatic cyst with no internal echoes. Bronchoscopy showed fresh blood and some necrotic material coming out of the superior segment of the right lower lobe. Culture of the material grew Aspergillus.
Wedge resection of the apical segment of the right lower lobe was performed due to persistent hemopty-sis and growth of Aspergillus species in a possible post tuberculous cavity. Gross examination of the specimen revealed a surprisingly whitish membrane of the cyst wall with fungal necrotic material inside ( Figure 2). Histopathological examination confirmed the pres-ence of hydatid cyst along with echinoccocus hooklets with invasive Aspergillus within the cyst wall ( Figure 2). Lung tissue around the cyst showed nonspecific chronic

Invasive aspergillosis of pulmonary hydatid cyst
Buzdar M. S. Nabi, a Kamran K. Chima, a Nauman Tarif, a Iltafat Sultan, b Syed Taifur-ul-Islam Gilani c inflammation and an absence of fungal hyphae. The pa-tient was treated for hydatid disease with albendazole and itraconazole for aspergillosis. The patient was free of any recurrence of either disease at the 8-month fol-low-up.

DIsCUssION
Pulmonary aspergilloma frequently complicates an ex-isting cavity that was due to tuberculosis in most cases. Nevertheless, aspergilloma can develop in any kind of pulmonary cavity, including cavities resulting from re-moval of a hydatid cyst. [1][2][3][4][5][6][7][8][9] Regnard et al reported growth of aspergilloma in a post-tuberculosis cavity in 69% of a series of 89 cases with aspergilloma. 4 Development of aspergilloma in hydatid cyst cavities is very rare. Aspergilloma in an operated hydatid cyst cavity was re-ported after many years in one case and after 6 months in another. 8,9 Our patient is unique in that a ruptured hydatid cyst and not a post-operative hydatid cavity was secondarily infected or co-infected with aspergilloma as shown on histopathology. In fact, the aspergilloma was seen invading the wall of the ruptured hydatid cyst. We could not identify any reported case in the literature showing invasive aspergillosis in the ruptured hydatid cyst. Hemoptysis is a common presentation in ruptured pulmonary hydatid cyst and also aspergilloma, which might be the cause in our patient. 7 We opted for wedge resection for recurrent hemoptysis since the surround-ing lung tissue was healthy and because this is recom-mended by others. 5 It has been reported that approximately 60% of pulmonary hydatid disease affects the right lung and 50% to 60% involves the lower lobes, which is consis-tent with the findings in our patient. 10 Hydatid disease has not been reported to develop in an already existing cavity and it is unlikely that it occurred in a post-tu-berculous cavity in our patient. Although it is specula-tive, histopathological examination did not support the

RefeReNCes
presence of a cavity. Whether the hydatid cyst ruptured spontaneously or because of the invasion of Aspergillus is again speculative. This might be supported by the fact that Aspergillus species grew in the sputum prior to bron-choscopy. In our patient, a CT scan showed a lamellar pattern that might suggest hydatid cyst; however, these findings can be confused between hydatid disease and aspergilloma. 7 Hepatic cysts also accompany 20% of the pulmonary hydatid disease cases. 10 Hepatic cyst was also noted in our patient, but did not have the characteristic features of hydatid hepatic cyst. The presence of hydatid cyst therefore came as a surprise. Furthermore, Aspergillus invading the wall of an active hydatid cyst is unique in this case and has never been reported in the literature.
In conclusion, in areas where hydatid disease is still a common occurrence, pulmonary hydatid cyst should be kept in mind before labeling each cavity as post-tuber-culous and aspergilloma as a secondary infection.