Stable pulmonary capillary haemangiomatosis without symptomatic pulmonary hypertension

Infantile pulmonary capillary haemangiomatosis: a lethal form of pulmonary hypertension

We describe the cases of two children who both presented in infancy with recurrent severe pulmonary hypertensive crises. Exhaustive clinical work-up failed to identify an underlying aetiology. The patients had no clinical response to steroids, immunoglobulins, or pulmonary vasodilators. Post-mortem examination revealed extensive invasive pulmonary capillary haemangiomatosis. There was no evidence of pulmonary venous occlusive disease. Given the lethal nature of this condition, early consideration of referral to a lung transplant centre should be considered in selected patients.

Pulmonary capillary hemangiomatosis: the role of invasive cardiopulmonary exercise testing

Pulmonary capillary hemangiomatosis (PCH) is a rare form of pulmonary arterial hypertension (PAH) characterized by pulmonary capillary proliferation and pseudoinvasion of collagenous septal structures. PCH is often accompanied by veno-occlusive changes and pulmonary hypertensive arterial remodeling. The clinical and pathological diagnosis of PCH can be subtle and easily missed. Most reported cases of PCH have been associated with resting PAH. We report the cases of 3 patients who initially presented with exertional dyspnea with normal to mildly elevated resting pulmonary arterial pressures and marked intrapulmonary shunting. In all 3 patients, invasive cardiopulmonary exercise testing was suggestive of pulmonary vascular disease. Owing to abnormalities on invasive exercise testing, lung biopsies were performed; these were diagnostic of PCH, and the patients were referred for lung transplantation. We describe unique features of these 3 cases-including novel pathological findings and the presence of intrapulmonary shunting in all 3 patients-and we discuss the role of cardiopulmonary exercise testing in the evaluation of PCH.

Pulmonary capillary hemangiomatosis: a focus on the EIF2AK4 mutation in onset and pathogenesis

Pulmonary capillary hemangiomatosis (PCH) is a pulmonary vascular disease that mainly affects small capillaries in the lung, and is often misdiagnosed as pulmonary arterial hypertension or pulmonary veno-occlusive disease due to similarities in their clinical presentations, prognosis, and management. In patients who are symptomatic, there is a high mortality rate with median survival of 3 years after diagnosis. Both idiopathic and familial PCH cases are being reported, indicating there is genetic component in disease etiology. Mutations in the eukaryotic translation initiation factor 2α kinase 4 (EIF2AK4) gene were identified in familial and idiopathic PCH cases, suggesting EIF2AK4 is a genetic risk factor for PCH. EIF2AK4 mutations were identified in 100% (6/6) of autosomal recessively inherited familial PCH and 20% (2/10) of sporadic PCH cases. EIF2AK4 is a member of serine/threonine kinases. It downregulates protein synthesis in response to a variety of cellular stress such as hypoxia, viral infection, and amino acid deprivation. Bone morphogenetic protein receptor 2 (BMPR2) is a major genetic risk factor in pulmonary arterial hypertension and EIF2AK4 potentially connects with BMPR2 to cause PCH. L-Arginine is substrate of nitric oxide synthase, and L-arginine is depleted during the production of nitric oxide, which may activate EIF2AK4 to inhibit protein synthesis and negatively regulate vasculogenesis. Mammalian target of rapamycin and EIF2α kinase are two major pathways for translational regulation. Mutant EIF2AK4 could promote proliferation of small pulmonary arteries by crosstalk with mammalian targets of the rapamycin signaling pathway. EIF2AK4 may regulate angiogenesis by modulating the immune system in PCH pathogenesis. The mechanisms of abnormal capillary angiogenesis are suggested to be similar to that of tumor vascularization. Specific therapies were developed according to pathogenesis and are proved to be effective in reported cases. Targeting the EIF2AK4 pathway may provide a novel therapy for PCH.

Pulmonary capillary haemangiomatosis in a premature infant

Pulmonary capillary haemangiomatosis (PCH) is a rare disorder characterized by widespread capillary proliferation in the lung, infiltrating the interstitium and the alveolar walls. We present the HRCT features of PCH in a surviving ex-premature infant. To our knowledge, this is a unique case of the radiological features of PCH in a young living infant.

Pulmonary capillary haemangiomatosis in children and adolescents: report of a new case and a review of the literature

Pulmonary capillary haemangiomatosis (PCH) in childhood is a rarity, characterised by the uncontrolled proliferation of pulmonary microvessels which may invade pulmonary, bronchial and vascular structures, resulting in diffuse alveolar haemorrhage, manifesting clinically in haemoptysis, dyspnoea and symptoms of pulmonary hypertension (PH). A 14-year-old boy with some particular features (pericardial effusion and thrombocytopenia) is presented and 14 paediatric/adolescent cases from the literature are surveyed. The diagnostic problems and difficulties are discussed, including the importance of imaging (high-resolution CT) and histopathological studies, with the aim of providing a clear-cut distinction of PCH from other conditions such as primary PH (PPH). The literature data can be regarded as ambiguous: both similarities and relatively sharp distinctions between PCH and PPH are to be found. New developments in the field of genetics are also discussed. The early coexistence of PCH and other (vascular) disorders and associations, involving focal or diffuse, disseminated forms is summarised briefly. Conclusion. The diagnosis of this progressive disorder may lead to effective therapy. Treatment possibilities include the rapidly evolving field of anti-angiogenic therapy, but at present lung transplantation is universally accepted as the final definitive treatment for pulmonary capillary haemangiomatosis.

Pulmonary capillary hemangiomatosis associated with primary pulmonary hypertension: report of 2 new cases and review of 35 cases from the literature

Pulmonary capillary hemangiomatosis (PCH) is a rare cause of primary pulmonary hypertension characterized by thin-walled microvessels infiltrating the peribronchial and perivascular interstitium, the lung parenchyma, and the pleura. These proliferating microvessels are prone to bleeding, resulting in accumulation of hemosiderin-laden macrophages in alveolar spaces. Here we report 2 cases of PCH with pulmonary hypertension, 1 of them associated with mechanical intravascular hemolysis, a feature previously reported in other hemangiomatous diseases, but not in PCH. Case 2 was diagnosed by pulmonary biopsy; to our knowledge the patient is the second adult to be treated with interferon alpha-2a. Review of the literature identified 35 patients with PCH and pulmonary hypertension. The prognosis is poor and median survival was 3 years from the first clinical manifestation. Dyspnea and right heart failure are the most common findings of the disease. Hemoptysis, pleural effusion, acropachy, and signs of pulmonary capillary hypertension are less common. Chest X-ray or computed tomography scan usually shows evidence of interstitial infiltrates, pulmonary nodules, or pleural effusion. Hemodynamic features include normal wedge pressures. Radiologic and hemodynamic findings are undifferentiated from those of pulmonary veno-occlusive disease but differ from other causes of primary pulmonary hypertension. Epoprostenol therapy, considered the treatment of choice in patients with primary pulmonary hypertension, may produce pulmonary edema and is contraindicated in patients with PCH. Regression of lesions was reported in 1 patient treated with interferon therapy and 2 other patients stabilized, including our second patient. PCH was treated successfully by lung transplantation in 5 cases. Early recognition of PCH in patients with suspected primary pulmonary hypertension is possible based on clinical and radiologic characteristics. Diagnosis by pulmonary biopsy is essential for allowing appropriate treatment.