Introduction
One of the most extensively dispersed colors in nature is tetrapyrroles. Besides serving as biological catalysts, they can also work as functional photoreceptors, potent photosensitizers, or potent quenchers of molecular excited states. The most significant tetrapyrrolic molecule found in animals is heme, which has little photobiological activity. Whether they stem from irregular heme biosynthesis, aberrant heme breakdown, or improper disposal of heme breakdown products, most human disorders linked to poor tetrapyrrole metabolism can be divided into groups. The illnesses that can lead to cutaneous photosensitivity are the most significant.
Porphyrias are illnesses that develop when the body has difficulty producing heme. These defects induce abnormal levels of porphyrins (which could cause photosensitivity) or porphyrin precursors to accumulate. Numerous processes and enzymes are involved in producing heme.
What Is Refsum Disease?
Refsum disease is an autosomal recessive neurological disorder that is brought on by an excessive buildup of phytanic acid in cells and tissues. Refsum disease patients exhibit peripheral neuropathy, cerebellar degeneration, and neurologic impairment. The disease typically begins in childhood or adolescence and progresses over time, with intervals of stagnation or remission. Ataxia, scaly skin (ichthyosis), difficulty hearing, and eye disorders such as retinitis pigmentosa, cataracts, and night blindness are all symptoms of Refsum disease.
What Causes Refsum Disease?
PHYH gene mutations account for more than 90 percent of all instances of Refsum disease. A gene called PEX7 has mutations that are responsible for the instances. This disease is inherited in an autosomal recessive form. Refsum illness is characterized by the aberrant accumulation of phytanic acid, a particular type of fatty acid. This chemical is consumed in food, mainly beef and dairy products. It generally undergoes a procedure called alpha-oxidation, which takes place in cellular organelles called peroxisomes. Enzymes that break down various chemicals, including fatty acids and some hazardous substances, are housed in these sac-like compartments.
Mutations in the PHYH or PEX7 gene impair the regular functions of peroxisomes, including the breakdown of phytanic acid. As a result, this substance builds up in the body's tissues. It is unknown whether excess phytanic acid harms cells and causes the other recognizable symptoms of Refsum sickness, but it appears to impact eyesight and smell.
What Are the Sign and Symptoms Associated With Refsum Disease?
1. A genetic disorder called Refsum disease results in visual loss, an absence of smell (anosmia), and a number of other signs and symptoms.
2. Retinitis pigmentosa is an eye condition contributing to Refsum disease-related vision loss. The retina, a light-sensitive layer in the back of the eye, is impacted by this condition. As the retina's light-sensing cells progressively degenerate leads to vision loss. Night vision loss frequently manifests in childhood and is typically the first indication of retinitis pigmentosa. The condition impairs side vision (peripheral vision) over time and may ultimately result in blindness.
Nearly all people with Refsum disease experience vision loss and anosmia, but other symptoms can vary that is:
3. Birth defects in the hands, feet, and bones.
4. Later-life characteristics include:
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Dry, scaly skin.
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Impaired balance.
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Coordination (ataxia).
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Gradual muscle weakness.
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Atrophy.
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Ataxia (ichthyosis).
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Hearing loss.
5. Also, some sufferers of Refsum disease experience life-threatening heart issues such as arrhythmia and an irregular heart rhythm.
What Are Hepatic Porphyrias?
Hepatic porphyrias are porphyrias in which poisonous porphyrin molecules accumulate in the liver. Porphyrins are chemicals that are required for the synthesis of heme. Heme is essential to the body and is in charge of the breakdown of drugs and other compounds. Acute hepatic porphyrias develop when the liver's heme synthesis is disrupted. When heme is not created properly, toxins like porphobilinogen and aminolevulinic acid build up in the liver and can spread throughout the body. Due to the accumulation of aminolevulinic acid and porphobilinogen toxin, the patient may experience painful attacks and other illness symptoms like nausea, vomiting, diarrhea, constipation, chest pain, muscle weakness, fatigue, rapid heartbeat, and seizures.
How is Hepatic Porphyria Treated?
Hepatic porphyria treatment focuses on preventing and treating symptom episodes. Therapy is more successful when healthcare providers can identify which triggers have the most impact.
Treatment includes:
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Hemin Injection - Hemin may be administered intravenously during a severe attack to assist in lowering the blood porphyrin levels. Hemin, a salt made from red blood cells, prevents the body from producing porphyrin.
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Pain Relief - During a severe attack, the patient could require powerful painkillers like opioids.
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Phenothiazines - These medications can relieve severe nausea and vomiting.
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Intravenous Fluid and Nutrition - During an attack, symptoms including abdominal discomfort, nausea, vomiting, diarrhea, and constipation may prevent the body from getting enough calories and liquids. Hepatic porphyria may result in sodium and magnesium shortages. The patient may be given electrolytes and carbohydrates in intravenous fluids.
Long-term treatment includes:
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Prophylactic Hemin - A weekly low dose of hemin may be helpful for people who have frequent episodes because it prevents porphyrins from accumulating.
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Givosiran - This drug prevents the synthesis of porphyrin precursors as a kind of gene therapy. Its use as a monthly injectable to prevent hepatic porphyria symptoms in those who experience frequent attacks has now received approval from the FDA (food and drug administration).
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Hormone Therapy - If a patient's menstrual cycle causes hepatic prophylaxis, a doctor may give GnRH (gonadotropin-releasing hormone) analogs, which block estrogen and progesterone production in the body.
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Liver Transplant - A liver transplant may be possible for those who frequently experience life-threatening episodes and do not respond to conventional forms of treatment.
Conclusion
The porphyrias display an autosomal-dominant pattern and typically have a family history of photodermatitis and stomach crises, concurrent mental and neurological problems, and reddish-brown, fluorescent urine. Hepatic porphyria can cause attacks that could be fatal, as well as chronic pain and other symptoms that make it difficult for some people to live regular lives. Hepatic porphyria has no known treatment, but there are techniques to control its symptoms. To prevent or treat hepatic porphyria attacks, doctors may recommend certain drugs approved by the United state FDA (food and drug administration). Painkillers and glucose supplements may also be used in disease management. When patients experience attacks that result in major medical problems like dehydration, hallucinations, paralysis, and breathing difficulties, treatment may occasionally entail hospital stays so that patients can be monitored and treated. Patients often have a history of remissions and exacerbations. To know more about the condition, consult the doctor online.
