Pulmonary hydatic disease presenting as solid mass with haemoptysis in a child

Abstract

A middle childhood HIV-negative female patient presented with three episodes of haemoptysis. The chest X-ray demonstrated an oval-shaped, well-circumscribed left upper lobe homogenous opacification. She did not respond to tuberculosis treatment. A left upper lobectomy was performed for a solid mass in the lung, and hydatic disease was histologically confirmed. Calcification was found in the pulmonary lesion. Pulmonary hydatic cyst rarely presents as a solid lesion with calcifications and haemoptysis.

Background

Pulmonary hydatidosis is the most frequently encountered type of hydatid disease in humans. It is endemic to many parts of the world, due to close contact between sheep and dogs and humans. Echinococcus species belong to the Taeniidae family of the Cestoda class in the Phylum Platyhelminthes and E. Granulosus is the most common and causes cystic echinococcosis.

Case presentation

A middle childhood HIV-negative female patient was admitted with the history of three episodes of haemoptysis and coughing with no associated symptoms of fever, vomiting or weight loss. She had a normal neonatal and childhood history and was not exposed to tuberculosis (TB).

Clinically her growth chart was normal with normal BMI, normal observations and not acutely or chronically ill. On respiratory evaluation, she had mildly reduced ventilation in the left upper lobe area.

Her routine laboratory investigations were normal and TB investigations (Mantoux and sputum ZN, Xpert MTB/RIF and culture) were negative.

The chest radiograph (figure 1A, B) revealed an oval-shaped, well-circumscribed left upper lobe homogenous opacification without any radiological visible airway compression.

Figure 1.

(A) Frontal and (B) lateral plain radiographs of the chest in a middle childhood girl presenting with haemoptysis, demonstrate a left upper zone oval density with well-demarcated borders, but no recognisable internal characteristics. There is no mediastinal or hilar lymphadenopathy and the airways are patent.

The differential diagnosis of solitary solid mass lesion included: congenital lesions (bronchogenic cyst), TB granuloma, round pneumonia, hydatic disease, pulmonary inflammatory pseudotumor, hamartoma, carcinoid, neuroblastoma, pleuropulmonary blastoma, solitary lung metastasis and pulmonary arteriovenous malformation.

She was started on a four-drug TB treatment in a rural hospital, based on the chest X-ray findings and the haemoptysis. Due to no proof for TB and persistent radiological findings, the patient was referred for chest CT-scan and bronchoscopy.

The contrasted CT scan (figure 2A–C) of the chest revealed a left upper lobe round and well-marginated heterogenous opacification measuring 30×20×25 mm. There were no visible air bronchograms, calcifications nor vascular supply in and to the lesion.

Figure 2.

CT chest with intravenous contrast in the same patient as figure 1 (A) axial soft-tissue window (B) axial lung window and (C) coronal reconstruction, confirms the left upper lobe oval mass with sharp margins and very little surrounding parenchymal reaction, and displacement of vessels around it. Internal density measures approximately 60–70 HU without any calcification. There are some areas of central lower density but no ring enhancement. No accompanying mediastinal or hilar lymphadenopathy.

A bronchoscopy and bronchoalveolar lavage were performed with a 4 mm Olympus video bronchoscope. The bronchoscopy findings showed a normal trachea-bronchial tree anatomy with generalised airway inflammation. The BAL Xpert MTB/RIF and culture were also negative.

BAL findings included the differential count: macrophages 80%, neutrophils 6%, lymphocytes 14% and eosinophils 0% and perl’s prussian blue for haemosiderin-laden macrophages was 1.6%.

A left mini thoracotomy was done with a bronchial blocker inserted into the left main bronchus.

The lung was palpated and there was a large, firm, centrally located mass in the left upper lobe. A left upper lobectomy was performed, and the specimen was sent for histology. Mediastinal lymph nodes were present.

Sections of the lung tumour (figure 3A–D) showed a cyst that, at least in areas, was lined by respiratory epithelium. The contents of the cyst consisted of acute inflammation in which the laminated wall of a hydatid cyst (echinococcus) was present.

Figure 3.

Image of the hydatid cyst. (A) A low power magnification showing a cyst that is lined by respiratory epithelium with the hydatid cyst in the lower half of the image with acute inflammation (H&E, 4x). (B) Shows a slightly higher magnification of a, with the blue arrow showing the laminated wall of the organism and the green arrow indicating the respiratory epithelium lining to the cyst (H&E, 10x). (C) Shows the ‘hydatid sand’ debris of the dead contents of the cyst with calcifications (H&E, 40x). (D) An echinococcus hooklet, with a shark-like appearance. These hooklets are made up of chitin and are more resistant to breakdown, hence they remain identifiable in the hydatid sand debris (H&E, 100x).

There was no viable daughter cyst present. Adjacent to the wall, there were calcifications and loose lying chitinous hooklets noted.

The surrounding lung parenchyma varied from normal to collapsed to areas of lipoid pneumonia. There were reactive lymph nodes with no signs of TB.

Serology was performed after the surgery and echinococcus IgG was positive. The child is not from an area where hydatic disease is endemic. The mother subsequently did give a history that they buy meat at a local abattoir in the town.

She made a full recovery with no long-term complications and normal chest X-ray. Abdominal ultrasound was performed to exclude liver involvement.

Treatment

Albendazole (15 mg/kg/day in two divided doses) was started after surgery and 1 month of treatment was completed.

Outcome and follow-up

She made a full recovery with no long-term complications and normal chest X-ray. Abdominal ultrasound was performed to exclude liver involvement. There were no further episodes of haemoptysis.

Discussion

Liver involvement is the most common presentation in adults compared with pulmonary involvement in the paediatric population. Children with echinococcosis may remain asymptomatic for many years and can last many years until a cyst has grown to a size that causes clinical signs or symptoms.¹ Small hydatid cysts in the lung often cause no symptoms, but large cysts may cause symptoms ranging from chest pain, coughing, dyspnoea, haemoptysis as well as allergic reactions including anaphylaxis.^2–5

Haemoptysis has rarely been reported but can present when the cyst gets infected or after rupture of the cyst into the airway. Calcification of pulmonary cysts is extremely rare especially in children. We present a case of hydatic disease presenting with haemoptysis, in which the CT scan showed a solid mass, and at surgery, a solid mass was found, not the typical cystic mass you expect from a hydatid cyst.

Learning points.

• Pulmonary hydatic disease should be considered in children presenting with solitary solid radiological lesion even if haemoptysis is present.

• Haemoptysis can present when the cyst gets infected or after rupture of the cyst into the airway.

• Hydatic disease can atypically present as a solid mass with calcifications on CT scan and at surgery.

Ethics statements

Patient consent for publication

Consent obtained from parent(s)/guardian(s)