Pulmonary capillary hemangiomatosis: report of a case and review of the literature

Vasoproliferative process resembling pulmonary capillary hemangiomatosis in a cat

BACKGROUND

Pulmonary capillary hemangiomatosis is a rare, vascular obstructive disorder that uniformly causes pulmonary arterial hypertension. Clinically, pulmonary capillary hemangiomatosis is indistinguishable from primary pulmonary arterial hypertension and histology is required for definitive diagnosis. The distinctive histologic feature of pulmonary capillary hemangiomatosis is non-malignant extensive proliferation of capillaries in the alveolar septae. Vasodilator treatment of humans with primary arterial hypertension due to pulmonary capillary hemangiomatosis can result in fatal acute pulmonary edema. Computed tomography is thus critical to discern pulmonary capillary hemangiomatosis from other causes of pulmonary arterial hypertension prior to vasodilator therapy. This is the first report of a vasoproliferative process resembling pulmonary capillary hemangiomatosis in the feline species.

CASE PRESENTATION

A 15-year-old, male castrated, domestic shorthair cat presented for persistent labored breathing presumptively due to congestive heart failure despite treatment with diuretics for 7 days. Echocardiography showed evidence of hypertrophic cardiomyopathy with severe pulmonary hypertension; however, a normal sized left atrium was not consistent with congestive heart failure. Thoracic computed tomography was performed and showed evidence of diffuse ill-defined nodular ground glass opacities, enlarged pulmonary arteries, and filling defects consistent with pulmonary thromboembolism. The cat acutely decompensated after a single dose of sildenafil and was euthanized. Histopathology of the lungs showed severe multifocal alveolar capillary proliferation with respiratory bronchiolar infiltration, marked type II pneumocyte hyperplasia and multifocal pulmonary arterial thrombosis.

CONCLUSION

This is the first description in a cat of a vasoproliferative disorder resembling pulmonary capillary hemangiomatosis complicated by multifocal pulmonary arterial thrombosis. Inspiratory and expiratory ventilator-driven breath holds with angiography revealed lesions predominantly characterized by ground glass opacification and vascular filling defects with absence of air trapping. The results from this report suggest that, as in humans, the cat can develop a pulmonary capillary hemangiomatosis-like disease in which vasodilator therapy to address pulmonary hypertension may lead to fatal pulmonary edema.

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.

A case of pulmonary capillary hemangiomatosis with pulmonary fibrosis associated with MMP-9 related pulmonary remodeling

Pulmonary capillary hemangiomatosis (PCH) is a rare cause of pulmonary hypertension. It is characterized capillary proliferation within the alveolar septa. Here, we report a case of PCH with extensive pulmonary fibrosis. A 52-year-old man with a clinical diagnosis of non-specific interstitial pneumonia died of respiratory failure with severe pulmonary hypertension. Autopsy revealed pronounced right ventricle hypertrophy and pulmonary fibrosis. Consistent with clinical diagnosis, histological examination revealed diffuse pulmonary fibrosis, in addition, it also disclosed marked capillary proliferation within the alveolar septa as well as the fibrotic pulmonary stroma, suggesting the presence of PCH. Hemosiderin-laden macrophages had accumulated in the capillary proliferative area, and bronchiolar-type metaplasia was conspicuous in the fibrotic lesion. Proliferated capillaries were surrounded by fine collagen and α-smooth muscle actin-positive myofibroblasts. Immunohistochemistry revealed that type IV collagen around capillaries in the area of the PCH without inflammation disappeared in the area with inflammation. In addition, the PCH lesion contained significant numbers of macrophages expressing matrix metalloproteinase (MMP) 9 and type II pneumocytes positive for vascular endothelial growth factor. Although pulmonary fibrosis is a distinctive disease entity, different from PCH, MMP-9-driven destruction of the basement membrane may promote unusual pulmonary remodeling, which, in this case, resulted in extensive pulmonary fibrosis.

From the Archives of the AFIP: pulmonary veno-occlusive disease and pulmonary capillary hemangiomatosis

Pulmonary veno-occlusive disease (PVOD) and pulmonary capillary hemangiomatosis (PCH) are two unusual idiopathic disorders that almost uniformly manifest to the clinician as pulmonary arterial hypertension (PAH). Impressive clinical signs and symptoms often obscure the true underlying capillary or postcapillary disorder, thus severely compromising timely and appropriately directed therapy. The hemodynamics of PVOD and PCH are the consequence of a widespread vascular obstructive process that originates in either the alveolar capillary bed (in cases of PCH) or the pulmonary venules and small veins (in PVOD). Since the earliest descriptions of PVOD and PCH, there has been a debate as to whether these are two distinct diseases or varied expressions of a single disorder. The cause of PVOD or PCH has not yet been identified, although there are several reported associations. Without curative lung or heart-lung transplantation, patients with these conditions face inexorable clinical deterioration and death within months to a few short years of initial presentation. Surgical lung biopsy is the definitive diagnostic test, but it is a risky undertaking in such critically ill patients. The imaging manifestations of PVOD and PCH often reflect the underlying hemodynamic derangements, and these findings may assist the clinician in discerning PAH from an underlying capillary or postcapillary process with findings of septal lines, characteristic ground-glass opacities, and occasionally pleural effusion.

Pulmonary capillary hemangiomatosis incidentally detected in a lobectomy specimen for a metastatic colon cancer

Pulmonary capillary hemangiomatosis is a rare vascular proliferative disease of unknown etiology. The common clinical features are slowly progressive and finally fatal pulmonary hypertension. The clinical diagnosis is usually difficult. Because most reported cases are of autopsy, little is known about its incipient lesion and natural history. Presented herein is a case of pulmonary capillary hemangiomatosis incidentally detected in a surgically resected lung for a metastatic colon cancer. The patient was a 60-year-old Japanese woman with a history of sigmoid colon cancer 3 years previously. The patient had undergone a right lower lobectomy for a metastatic tumor in the hilar region and a thoracoscopic tumorectomy of the peripheral area of the left upper lobe. Except for an episode of hemoptysis 2 weeks prior to the lung surgery, there were no other clinical symptoms characteristic of pulmonary capillary hemangiomatosis. The non-tumor area of right lower lobe showed multiple foci of capillary proliferation affecting alveolar walls, interlobular septa and pleura associated with patchy hemorrhage. There was a minor degree of vascular and bronchial involvement by capillary proliferation. It is suggested this particular case is an incidentally detected clinically incipient stage of pulmonary capillary hemangiomatosis. Passive congestion secondary to metastatic colon cancer in the hilar region may have contributed to the pathogenesis of this lesion.

Hemangiomatose capilar pulmonar, uma rara causa de hipertensão pulmonar: primeiro caso brasileiro

A hemangiomatose capilar pulmonar é uma doença rara, caracterizada por proliferação de capilares que invadem o interstício pulmonar e o septo alveolar. Documentamos o primeiro caso brasileiro: um paciente do sexo masculino, de 21 anos, com hipertensão pulmonar grave, que evoluiu para óbito. Na tomografia computadorizada de alta resolução apresentava pequenas opacidades intersticiais nodulares maldefinidas, bilateralmente. Foi realizada biópsia pulmonar post-mortem e encontrada intensa proliferação multifocal de capilares nas paredes alveolares, septos interlobulares e tecido conjuntivo peribrônquico. O diagnóstico de hemangiomatose capilar pulmonar deve ser considerado nos pacientes com hipertensão pulmonar e alterações sugestivas na tomografia computadorizada de alta resolução.

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 Hemangiomatosis With Atypical Endotheliomatosis *

We report here our experience in achieving remission in a 20-year-old man with pulmonary capillary hemangiomatosis (PCH) with atypical endotheliomatosis following therapy with doxycycline. PCH is a rare disorder characterized by proliferating capillaries that invade the pulmonary interstitium and alveolar septae, and occlude the pulmonary vasculature. The patient's symptoms, lung function, and radiographic findings had worsened despite treatment with both prednisone and alpha-interferon. He was considered to be a candidate for transplantation. Given the elevated levels of basic fibroblast growth factor (bFGF) in urine and the capillary proliferation noted on biopsy specimens, we elected to treat the patient with doxycycline, a matrix metalloproteinase and angiogenesis inhibitor. Following several weeks of therapy, a gradual resolution of symptoms was noted, with normalization of pulmonary function test results and urine bFGF levels. After 18 months of therapy, the patient remains in complete remission.

Congenital pulmonary capillary hemangiomatosis: Report of two cases and review of the literature

Pulmonary capillary hemangiomatosis (PCH) is a rare disease characterized by pulmonary hypertension and excessive neovascularization within the pulmonary interstitium, vasculature, and airways. We describe two unusual cases of congenital PCH. Both cases had concurrent anomalies, including renal and urinary bladder agenesis and hypertropic cardiomyopathy. In one case, capillary proliferation caused significant impingement of the proximal bronchial airways. A review of the current literature is described.

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.

Fetal constrictive pericardial defect with pulmonary capillary hemangiomatosis

Pericardial defect is a rare anomaly that has a variable presentation. Prompt recognition and early surgical intervention are associated with a favorable outcome. The authors present an unusual case of unexpected fetal demise in a 31-week-gestational-age girl who had a large pericardial defect forming a constrictive ring around both ventricular chambers. The defect coexisted with pulmonary capillary hemangiomatosis, an association that has not been reported in cases of pericardial defect.

Multifocal distribution of pulmonary capillary haemangiomatosis

AIMS

We investigated a case of pulmonary capillary haemangiomatosis, a rare condition, to determine the extent of the pathological changes within the lungs. Systematic histological sampling has not previously been performed in this condition.

METHODS AND RESULTS

A 52-year-old woman with a history of ischaemic cardiomyopathy suffered from repeated respiratory infections, which were attributed to chronic pulmonary congestion. She died suddenly of fulminant pulmonary thromboembolism. An autopsy was performed and lung tissue was sampled at multiple sites. Beside passive congestion, the lungs showed well-circumscribed areas containing proliferations of small capillaries infiltrating the pulmonary septa and the walls of otherwise normal blood vessels and bronchi. The most severely affected areas were found to be in the periphery of both lower lobes. A diagnosis of pulmonary capillary haemangiomatosis was made.

CONCLUSIONS

This is the first case of pulmonary capillary haemangiomatosis in which systematic histological sampling has been performed. Mapping of lesions disclosed the multifocal distribution of pulmonary capillary haemangiomatosis in this patient.

Pulmonary capillary hemangiomatosis-like foci. An autopsy study of 8 cases

Pulmonary capillary hemangiomatosis (PCH) typically occurs in young patients who have signs and symptoms of pulmonary hypertension. It commonly is misdiagnosed in life as pulmonary veno-occlusive disease, and the correct diagnosis usually is not made until autopsy. Autopsy records, including reports, gross photographs, histologic slides, clinical histories, and radiographic images, were reviewed to identify cases with morphologic changes characteristic of PCH. The previous case reports describe PCH as a diffuse process throughout both lung fields. All patients were symptomatic, and most died of the disease. This article details 8 cases of PCH-like foci that were incidental findings at autopsy in which the patients did not have symptoms of pulmonary hypertension nor did PCH contribute in any way to death. This is the first case series that describes pathologic changes of PCH occurring in this setting, and we hope to provide more interest in PCH and its natural history.

Pulmonary capillary hemangiomatosis as a rare cause of pulmonary hypertension

Pulmonary capillary hemangiomatosis (PCH), first described by Wagenvoort et al. in 1978, is a rare cause of pulmonary hypertension which occurs predominantly in young adults. In the literature only 18 cases have been reported. In 1988 Langleben et al. proposed a hereditary form of PCH with probable autosomal-recessive transmission. Histologic findings include irregular small nodular foci of thin-walled capillary-sized vessels which diffusely invade the lung parenchyma, the bronchial/bronchiolar walls and the adventitia of large vessels. We report on a case of PCH in a 24 year old man who presented the clinical signs of interstitial lung disease.

[Transtracheal catheter and liquid oxygen: 5 years of experience]

We studied clinical tolerance, complications, change in pulmonary function test results, arterial gasometrics, hemoglobin (Hb), 6 minute stress tests (6 wt) and subjective perception of dyspnea assessed on a visual analog scale (VAS) in a group of 18 patients (17 with obstructive disease and one with restrictive disease). These patients had previously been enrolled in a home oxygen therapy (HOT) program to deliver continuous oxygen therapy through nasal prongs, and had accepted portable oxygen therapy delivered by transtracheal catheter (TTC) from 1988 until 1993. Tolerance was good, there were no lethal complications of TTC, and excellent compliance with the prescribed HOT was achieved. Lung function test results worsened, while Hb and PaO2 improved and significant oxygen savings (50%) were achieved. The 6 wt test results had not worsened at the end of the first year but did so significantly at the end of the third year, in spite of a relative preservation of lung function. Dyspnea assessed on a VAS was not seen to worsen. We conclude that tolerance of the method was good and that no relevant complications occurred. HOT by TTC did not prevent worsening of bronchial obstruction. Oxygenation of patients was better, as shown by the decrease in Hb and the improvement in PaO2 at the end of the first year of monitoring. Changes in 6 wt showed that in order to achieve greater benefit from HOT by TTC, patients should follow a pulmonary rehabilitation program.