hereditary sensory and autonomic neuropathy type 1C

Hereditary Sensory and Autonomic Neuropathy Type 1C (HSAN1C) is a rare autosomal dominant neurologic disorder characterized by sensory neuropathy with variable involvement of the autonomic nervous system [2][3]. The condition primarily affects the distal regions of the extremities, leading to reduced ability to sense pain, temperature, touch, and vibration stimuli [1].

The symptoms of HSAN1C can vary in severity and may include:

• Distal sensory impairment: Reduced sensation in the hands and feet
• Autonomic disturbances: Some patients may experience autonomic dysfunction, which can affect various bodily functions such as heart rate, blood pressure, and digestion

HSAN1C is a slowly progressive neurological disorder that affects individuals of all ages. The condition is inherited in an autosomal dominant pattern, meaning that a single copy of the mutated gene is sufficient to cause the disease [5][9].

It's worth noting that HSAN1C is one of several types of hereditary sensory and autonomic neuropathies (HSANs), which are characterized by abnormalities affecting the nerves. The exact prevalence and clinical features of HSAN1C can vary, but it is generally considered a rare condition [6].

Hereditary sensory and autonomic neuropathy type 1C (HSAN1C) is a rare neurological disorder characterized by prominent distal sensory loss, autonomic disturbances in some patients, and other specific symptoms. The signs and symptoms of HSAN1C can vary widely from one person to another.

Main Features:

• Sensory Loss: Patients with HSAN1C typically experience sensory loss, which can manifest as numbness, tingling sensations (paresthesias), or a reduced ability to feel pain and sense hot and cold [2].
• Distal Limb Weakness: Many people with this condition experience distal limb weakness, which can lead to muscle atrophy [3].
• Autonomic Dysfunction: Some patients may also experience autonomic disturbances, such as sweating disturbances [8].

Additional Symptoms:

• Numbness and Tingling: Patients often report numbness or tingling sensations in their hands and feet.
• Pain Sensitivity: Some individuals with HSAN1C may have a reduced ability to feel pain.
• Muscle Atrophy: Distal muscle atrophy can occur, particularly in the limbs.
• Skin Ulcers: Variable distal muscle weakness and wasting, as well as chronic skin ulcers, are characteristic symptoms [8].

Age of Onset:

• Most patients experience adult onset of slowly progressive distal sensory impairment, manifesting as numbness, tingling, or pain, as well as distal muscle atrophy [6].

It is essential to note that specific symptoms can vary widely from one person to another, and the condition is inherited as an autosomal dominant trait due to mutations in specific genes [4].

Hereditary Sensory and Autonomic Neuropathy (HSAN) type 1C is a rare genetic disorder that affects the nervous system. Diagnostic tests for HSAN type 1C are crucial in confirming the diagnosis and ruling out other conditions.

Genetic Testing The primary diagnostic test for HSAN type 1C is genetic testing, which involves analyzing the SPTLC2 gene [1]. This test can confirm the presence of a mutation in the SPTLC2 gene, which is associated with HSAN type 1C. Genetic testing can be performed on blood samples or other tissues.

Clinical Evaluation A thorough clinical evaluation by a neurologist or geneticist is also essential in diagnosing HSAN type 1C [4]. This involves a detailed medical history, physical examination, and neurological assessment to rule out other conditions that may present with similar symptoms.

Other Diagnostic Tests While not specific to HSAN type 1C, other diagnostic tests such as nerve conduction studies (NCS) and electromyography (EMG) can help assess the function of the nerves and muscles [4]. These tests can provide valuable information about the extent of nerve damage and muscle involvement.

Genetic Panels Some genetic panels, such as the Invitae Hereditary Sensory and Autonomic Neuropathy Panel, analyze multiple genes associated with HSANs, including SPTLC2 [5]. These panels can be useful in identifying mutations in other genes that may contribute to the development of HSAN type 1C.

In summary, diagnostic tests for HSAN type 1C include genetic testing (SPTLC2 gene analysis), clinical evaluation by a neurologist or geneticist, and other supportive tests such as NCS and EMG. Genetic panels can also be useful in identifying mutations in other genes associated with HSANs.

References: [1] Context result 1: The Invitae Hereditary Sensory and Autonomic Neuropathy Panel analyzes genes associated with hereditary sensory and autonomic neuropathies (HSANs), including SPTLC2. [4] Context result 4: Three affected members were evaluated by neurological examination, nerve conduction study (NCS), and genetic testing. [5] Context result 5: This panel analyzes 20 genes, including the most common genetic causes of Hereditary Sensory and Autonomic Neuropathy (HSAN).

Hereditary Sensory Neuropathy Type 1 (HSAN1) is a rare genetic disorder that affects the nervous system, leading to sensory and autonomic dysfunction. While there are no specific treatments for HSAN1, research has identified some potential therapeutic options.

Targeted Treatment A targeted treatment for HSAN1 has been discovered, which involves taking extra-large doses of L-serine, a normal dietary amino acid [5]. This treatment has shown significant improvement in symptoms and nerve function in patients with HSAN1 [7].

Pharmacological Treatments Research has also explored the effectiveness of pharmacological treatments for hereditary peripheral neuropathies, including HSAN1. While no specific treatment is mentioned for HSAN1C, tafamidis, patisiran, inotersen, and diflunisal have shown significant benefit in high-quality evidence for Transthyretin-related amyloid neuropathy [1].

Gene-Based Treatments Gene-based treatments are also being explored for hereditary peripheral neuropathies. However, no specific treatment is mentioned for HSAN1C.

It's essential to note that these findings are based on limited research and more studies are needed to confirm the effectiveness of these treatments for HSAN1C specifically.

References: [1] by MJ Jennings · 2021 · Cited by 14 — In TTR-related amyloid neuropathy, four treatments (tafamidis, patisiran, inotersen and diflunisal) showed significant benefit in high quality ... [5] A targeted treatment for HSAN1 has been discovered . A normal dietary amino acid, L-serine, when taken in extra-large doses improved symptoms and nerve function ... [7] by MJ Jennings · 2021 · Cited by 14 — Treatment with L-serine in 18 patients with SPTLC1 variants resulted in significant decrease in CMTNS scores compared to placebo.

Hereditary sensory and autonomic neuropathy type 1C (HSAN1C) can be challenging to diagnose due to its similarity with other conditions. A differential diagnosis is essential to rule out other possible causes of the symptoms.

According to various studies, the differential diagnosis for HSAN1C includes:

• Other hereditary sensory and autonomic neuropathies (HSAN): Specifically, HSAN II is a rare genetic disorder that affects the nerves serving the lower arms and hands, as well as the lower legs and feet. It shares similar symptoms with HSAN1C, such as numbness, tingling, and reduced sensation.
• Diabetic foot syndrome: This condition can also present with sensory loss and distal muscle weakness, making it a potential differential diagnosis for HSAN1C.

It's essential to consider these conditions when diagnosing HSAN1C. A thorough medical history, physical examination, and diagnostic tests such as nerve conduction studies (NCS) and electromyography (EMG) can help differentiate between these conditions.

References:

• [3] Hereditary sensory neuropathy type I (HSN I) is a slowly progressive neurological disorder characterised by prominent predominantly distal sensory loss, autonomic disturbances, autosomal dominant inheritance, and juvenile or adulthood disease onset. The exact prevalence is unknown, but is estimated as very low.
• [4] Differential diagnosis includes the other hereditary sensory and autonomic neuropathies (HSAN), especially HSAN II, as well as diabetic foot syndrome.
• [9] HEREDITARY SENSORY & AUTONOMIC NEUROPATHIES (HSAN) · Nerve pathology: Axon loss · NCV: Axon loss · Muscle pathology: Type grouping; Grouped atrophy · Brain MRI: