Idiopathic pulmonary haemosiderosis

A 6-year-old African American female patient presented with a 3-week history of cough unresponsive to treatment with antibiotics. The patient was born prematurely at 28 weeks and was below the 5th percentile for height and weight at presentation. She has a history of gastro-esophageal reflux disease, aspiration, and recurrent colds.

A frontal chest radiograph (Fig.1) demonstrates bilateral middle and lower lung predominant airspace opacities. Non-contrasted axial CT-images (Fig. 2) obtained a few days later demonstrated multifocal ground glass opacities with denser areas of airspace consolidation scattered throughout the bilateral lungs.

Background:
Idiopathic Pulmonary Haemosiderosis (IPH) is a rare condition in which the patient suffers from recurrent episodes of diffuse alveolar haemorrhage of unknown aetiology [1]. The pulmonary system responds to haemorrhage via activation of alveolar macrophages. These specialised macrophages phagocytose erythrocytes at a rate six times slower than systemic macrophages [2]. This reduced ability to metabolise the haemorrhaged blood ultimately leads to a build-up of haemosiderin [2].

Clinical Perspective:
The pulmonary haemorrhage of IPH gives rise to the symptoms commonly seen in this condition. The clinical course is defined by unpredictable alternations between acute and chronic phases. In the acute phase, alveolar haemorrhage presents as dyspnoea, cough and haemoptysis and is sometimes referred to as an IPH exacerbation. Patients in the chronic phase have similar but slowly resolving symptoms [1].

This patient suffered from all symptoms except for haemoptysis. Imaging is ordered as a non-invasive means of discovering whether the symptom profile is derived from bleeding within the lung tissue [3]. Serology is used in order to exclude autoimmunity, vasculitides, and other potential causes [1]. Pathology is used to confirm the diagnosis of IPH [1].

Imaging Perspective:
Thoracic radiographs are ordered to evaluate for lung opacities that may indicate pulmonary haemorrhage [3]. A thoracic CT is ordered to better characterise and localise the suspected bleed [3]. CT shows ground glass opacities often predominating in the lower lobes [3]. Imaging is paramount to reaching the diagnosis of IPH because it rules out causes of haemorrhage apparent on imaging and allows the surgeon to target the correct pathologic sites for bronchoalveolar lavage (BAL) and peripheral wedge biopsy. The BAL revealed haemosiderin-laden macrophages. The open lung biopsy also showed haemosiderin-laden macrophages with minimal lymphocytic infiltrate and scattered alveolar wall fibrosis. Serologic testing was negative.

Outcome:
IPH is commonly treated with glucocorticoids plus or minus addition of immunosuppressants [4]. She was given oral prednisone and iron supplementation and nutritional advice for the anaemia and low weight, albuterol and fluticasone for asthma, omeprazole for her GERD. The rarity of IPH makes the prognosis difficult to determine although it is believed that children suffer a more aggressive course compared to adults [5]. In conclusion, this patient presented at the peak incidence of childhood with all 3 of the key symptoms of IPH, serology was negative, and pathology confirmed the diagnosis. The patient is doing well with treatment 10 years after diagnosis.