Porphyria is in most cases an inherited disease, manifested by, among others, photophobia. For this reason, it was once associated with vampirism. Porphyria has many types, it is incurable, but we already know how to mitigate its effects and severe, sometimes fatal attacks. What are the causes and symptoms of porphyria? How is the treatment going?

Porphyrias are a group of genetic metabolic diseases related to heme synthesis disorders and resulting in the accumulation of excessive amounts of porphyrins or their precursors in the body. Most heme is synthesized in cells of the erythroblastic lineage to be used in the production of hemoglobin. Everything else is synthesized in the liver.

Porphyry - classification

We divide porphyrias according to the organ in which the enzymatic defect was revealed:

      • Erythropoietic porphyrias - disorders mainly affecting the skin
      • hepatic porphyria - disorders of the nervous system

Another method of division is based on the course of the disease and distinguishes:

      • acute porphyria such as: acute intermittent porphyria, ALA dehydratase deficiency, congenital coproporphyria, mixed porphyria
      • cutaneous porphyria, for example: cutaneous late porphyria, hepato-erythropoietic porphyria, erythropoietic protoporphyria and congenital erythropoietic porphyria

Acute intermittent porphyria

Acute intermittent porphyria is the most common acute porphyria. It is inherited autosomal dominantly and is caused by deficiency of porphoblinogen deaminase.
Acute intermittent porphyria - symptoms:

The disease is asymptomatic in many cases. Factors that increase the synthesis of porphyrins, such as contraceptives, alcohol, smoking or marijuana, a slimming diet, infection, stress, surgery, some medications, contribute to inducing a seizure. Typical symptoms are:

      • paroxysmal abdominal pain with vomiting and diarrhea or constipation
      • neuropathies, paralysis and hyperalgesia
      • urination disorders
      • fever, sweating
      • tachycardia
      • hypertension
      • mental symptoms that may herald an impending attack, such as confusion, insomnia, anxiety, depression and hallucinations

Acute intermittent porphyria - diagnosis

The most useful parameter for the diagnosis of this disorder is the increased excretion of ALA and PBG in the urine during an attack. Other supporting studies include:

      • blood test usually showing hyponatraemia, hypomagnesaemia and leukocytosis
      • enzyme test to prove the reduction of PBG deaminase activity
      • EKG
      • Abdominal X-ray

Acute intermittent porphyria - treatment

It is very important to avoid factors that increase porphyrin synthesis and trigger seizures. Each patient should be familiar with the list of medications that should not be taken, and take care of a proper diet that provides a sufficient amount of calories and carbohydrates.

In the event of an acute attack, the patient should report to the hospital. Symptomatic drugs are:

      • painkillers such as paracetamol and opioid analgesics
      • antihypertensive drugs in the form of beta-blockers
      • drugs for nausea and vomiting: phenothiazines, ondansetron
      • in the treatment of infections the following are used: penicillins, cephalosporins, aminoglycosides

Mixed porphyria

Mixed porphyria is the most common disease in South Africa. It is inherited autosomal dominantly and is caused by decreased activity of protoporphyrinogen oxidase.
Mixed porphyria - symptoms

Often one of the symptoms of porphyria is hypersensitivity to sunlight, which in the past was associated with vampires. Other symptoms include the characteristic neuromuscular symptoms:

      • paroxysmal abdominal pain
      • neuropathies and paralysis

Mixed porphyria - diagnosis

The tests performed to diagnose mixed porphyria include:

      • urine test showing increased ALA, PBG and coproporphyrin excretion
      • stool examination also characterized by an increase in the excretion of coproporphyrins as well as protoporphyrins
      • study of the fluorescent emission of the plasma porphyrin spectrum

Mixed porphyria - treatment

Treatment for mixed porphyria is the same as for acute intermittent porphyria.

Late cutaneous porphyria

Late cutaneous porphyria is the most common porphyria in Europe. It may be an acquired disease or an autosomal dominant inherited disease. The cause of this disorder is deficiency of uroporphyrinogen decarboxylase. The consequence of this is accumulationthe formation of uroporphyrin and the 7-carboxylic porphyrin. Iron also accumulates in hepatocytes.
Late cutaneous porphyria - symptoms

Late cutaneous porphyria may be asymptomatic or manifest itself mainly in the form of skin changes, such as;

      • sensitivity of the skin to light, which causes blistering and blistering, especially in the face, back of the hands and feet, and on the shins and forearms
      • erosions
      • decay changes
      • scars
      • skin discoloration
      • hair growth

In addition to skin symptoms, liver enlargement may occur. The acquired form of this porphyria is revealed as a result of alcohol abuse, the use of contraceptives, iron supplements, or in the course of an infection.
Late cutaneous porphyria - diagnosis

The most important research proving the presence of the disease are:

      • stool test to reveal isocoproporphyrin excretion
      • urine test showing the excretion of uroporphyrins and 7-carboxylic porphyrins in the urine

Among other recommended studies are:

      • study of the biochemical features of liver damage
      • blood test for increased iron and ferritin levels
      • histological examination of the liver

Late cutaneous porphyria - treatment

As with other porphyria, it is important to avoid factors that increase heme synthesis.

In addition, blood depletion is used to reduce the iron stores in the liver. Typically, about 450 ml of blood is dropped during a single treatment. Treatment with chloroquine sulfate can be used when this method is contraindicated.

Category:

Genetic diseases