Pulmonary veno-occlusive disease (PVOD) is a rare form of pulmonary hypertension caused by progressive blockage of the small veins in the lungs. The blockage leads to high blood pressures in the arteries of the lungs, which, in turn, leads to

heart failure Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, a ...

. The disease is progressive and fatal, with median survival of about 2 years from the time of diagnosis to death. The definitive therapy is

lung transplantation Lung transplantation, or pulmonary transplantation, is a surgical procedure in which one or both lungs are replaced by lungs from a donor. Donor lungs can be retrieved from a living or deceased donor. A living donor can only donate one lung lobe. ...

Signs and symptoms

The symptoms for pulmonary veno-occlusive disease are the following:

Cause

The genetic cause of pulmonary veno-occlusive disease is

mutations In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mi ...

EIF2AK4 Eukaryotic translation initiation factor 2-alpha kinase 4 is an enzyme that in humans is encoded by the ''EIF2AK4'' gene. EIF2AK4 belongs to a family of kinases that phosphorylate the alpha subunit of eukaryotic translation initiation factor-2 (E ...

gene. Though this does not mean other possible causes do not exist, such as viral infection and risk of toxic chemicals (

chemotherapy Chemotherapy (often abbreviated to chemo and sometimes CTX or CTx) is a type of cancer treatment that uses one or more anti-cancer drugs (chemotherapeutic agents or alkylating agents) as part of a standardized chemotherapy regimen. Chemotherap ...

drugs).

Pathophysiology

Pulmonary veno-occlusive disease may have a genetic basis. Published reports have indicated fatal occurrences that appeared to possess a familial pattern, more to the point, a

germline In biology and genetics, the germline is the population of a multicellular organism's cells that pass on their genetic material to the progeny (offspring). In other words, they are the cells that form the egg, sperm and the fertilised egg. They ...

mutation. The pathophysiology of veno-occlusive disease culminates in occlusion of the pulmonary

blood vessels The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away f ...

. This could be due to

edematous Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels tight, the area ma ...

tissue (sclerotic

fibrous Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate ...

tissue). Thickening is identified in

lobular In anatomy, a lobe is a clear anatomical division or extension of an organ (as seen for example in the brain, lung, liver, or kidney) that can be determined without the use of a microscope at the gross anatomy level. This is in contrast to the muc ...

septal veins, also dilatation of

lymphatics The lymphatic vessels (or lymph vessels or lymphatics) are thin-walled vessels (tubes), structured like blood vessels, that carry lymph. As part of the lymphatic system, lymph vessels are complementary to the cardiovascular system. Lymph vessel ...

happens. Furthermore, alveolar

capillaries A capillary is a small blood vessel from 5 to 10 micrometres (μm) in diameter. Capillaries are composed of only the tunica intima, consisting of a thin wall of simple squamous endothelial cells. They are the smallest blood vessels in the body: ...

become dilated (due to back-pressure).

Diagnosis

Pulmonary veno-occlusive disease can only be well diagnosed with a lung biopsy.

CT scans A computed tomography scan (CT scan; formerly called computed axial tomography scan or CAT scan) is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers ...

may show characteristic findings such as

ground-glass opacities Ground-glass opacity (GGO) is a finding seen on chest x-ray (radiograph) or computed tomography (CT) imaging of the lungs. It is typically defined as an area of hazy opacification (x-ray) or increased attenuation (CT) due to air displacement ...

in centrilobular distribution, and

mediastinal lymphadenopathy Mediastinal lymphadenopathy or mediastinal adenopathy is an enlargement of the mediastinal lymph nodes. Causes There are many possible causes of mediastinal lymphadenopathy, including: *Tuberculosis *Sarcoidosis *Lung cancer/oesophageal cancer *L ...

, but these findings are non-specific and may be seen in other conditions. However, pulmonary hypertension (revealed via physical examination), in the presence of

pleural effusion A pleural effusion is accumulation of excessive fluid in the pleural space, the potential space that surrounds each lung. Under normal conditions, pleural fluid is secreted by the parietal pleural capillaries at a rate of 0.6 millilitre per kilog ...

(done via CT scan) usually indicates a diagnosis of pulmonary veno-occlusive disease. The prognosis indicates usually a 2-year (24 month) life expectancy after diagnosis.

Treatment

Treatments for primary pulmonary hypertension such as

prostacyclin Prostacyclin (also called prostaglandin I2 or PGI2) is a prostaglandin member of the eicosanoid family of lipid molecules. It inhibits platelet activation and is also an effective vasodilator. When used as a drug, it is also known as epoprosteno ...

s and

endothelin receptor antagonist An endothelin receptor antagonist (ERA) is a drug that blocks endothelin receptors. Three main kinds of ERAs exist: * selective ETA receptor antagonists ( sitaxentan, ambrisentan, atrasentan, BQ-123, zibotentan, edonentan), which affect e ...

s can be fatal in people with PVOD due to the development of severe

pulmonary edema Pulmonary edema, also known as pulmonary congestion, is excessive edema, liquid accumulation in the parenchyma, tissue and pulmonary alveolus, air spaces (usually alveoli) of the lungs. It leads to impaired gas exchange and may cause hypoxemia an ...

, and worsening symptoms after initiation of these medications may be a clue to the diagnosis of pulmonary veno-occlusive disease. The definitive therapy is

, though transplant rejection is always a possibility, in this measures must be taken in terms of appropriate treatment and medication.

Epidemiology

Pulmonary venoocclusive disease is rare, difficult to diagnose, and probably frequently misdiagnosed as idiopathic pulmonary arterial hypertension. Prevalence in parts of Europe is estimated to be 0.1-0.2 cases per million. PVOD appears to occur as frequently in men as in women, and age at diagnosis ranges from 7–74 years with a median of 39 years. PVOD may occur in patients with associated diseases such as

HIV The human immunodeficiency viruses (HIV) are two species of ''Lentivirus'' (a subgroup of retrovirus) that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the immune ...

bone marrow transplantation Hematopoietic stem-cell transplantation (HSCT) is the transplantation of multipotent hematopoietic stem cells, usually derived from bone marrow, peripheral blood, or umbilical cord blood in order to replicate inside of a patient and to produc ...

, and

connective tissue disease A connective tissue disease (collagenosis) is any disease that has the connective tissues of the body as a target of pathology. Connective tissue is any type of biological tissue with an extensive extracellular matrix that supports, binds togeth ...

s. PVOD has also been associated with several

regimens such as

bleomycin -13- (1''H''-imidazol-5-yl)methyl9-hydroxy-5- 1''R'')-1-hydroxyethyl8,10-dimethyl-4,7,12,15-tetraoxo-3,6,11,14-tetraazapentadec-1-yl}-2,4'-bi-1,3-thiazol-4-yl)carbonyl]amino}propyl)(dimethyl)sulfonium , chemical_formula = , C=55 , H=84 , N=1 ...

, BCNU, and

mitomycin The mitomycins are a family of aziridine-containing natural products isolated from ''Streptomyces caespitosus'' or ''Streptomyces lavendulae.'' They include mitomycin A, mitomycin B, and mitomycin C. When the name mitomycin occurs alone, it usually ...

Society

Chloe Temtchine Chloe Temtchine is an American singer-songwriter. Early life Temtchine grew up in New York City. She studied at Berklee College of Music, in Boston, Massachusetts. She started singing when she was six years old. At the time, on Sundays, her fath ...

, American singer-songwriter with PVOD

References

External links

{{Vascular diseases Cardiovascular diseases Lung disorders