Rheumatic diseases often involve the nervous system, the following is a brief introduction to the neurological manifestations of rheumatic diseases. 1. Systemic lupus erythematosus (SLE): It is an autoimmune-mediated, diffuse connective tissue disease with immune inflammation as the prominent manifestation. Neurological damage: also known as neuropsychiatric lupus. In mild cases, only migraine, personality changes, memory loss or mild cognitive impairment are observed; in severe cases, coma and epilepsy may be manifested. Central nervous system manifestations include aseptic meningitis, cerebrovascular disease, movement disorders, myelopathy, seizures, anxiety and psychiatric disorders; peripheral nervous system manifestations include Green-Barre syndrome, dysfunction of the vegetative nervous system, mononeuropathy, myasthenia gravis, cranial neuropathy, plexopathy, polyneuropathy, etc. In the presence of one or more of these manifestations, and excluding secondary factors such as infection and drugs, neuropsychiatric lupus can be diagnosed in combination with imaging, cerebrospinal fluid and electroencephalography. 2. Polymyositis and dermatomyositis:Polymyositis and dermatomyositis are non-suppurative inflammatory myopathies of skeletal muscle. Polymyositis refers to the absence of skin damage, such as myositis with rash is called dermatomyositis. The early symptoms of the disease are proximal muscle weakness or rash, fever, malaise, and weight loss. Muscular and neurological manifestations: The disease involves the transverse muscles and is characterized clinically by weakness of the proximal muscles, often with symmetrical damage, and there may be muscle swelling and pressure pain in the early stages and muscle atrophy in the late stages. Muscle weakness: Almost all patients present with varying degrees of muscle weakness. Shoulder girdle muscle and proximal upper limb muscle weakness: upper limbs cannot be lifted flat or up, combing or threading the head. Pelvic girdle muscle and thigh muscle weakness: inability or difficulty to lift the leg, inability to get into a car, go upstairs, sit down or get up after squatting. The cervical flexors can be severely involved: difficulty in raising the head in a flat position, and the head is often tilted back. Weakness of the laryngeal muscles causes difficulty in articulation and hoarseness. The involvement of the transverse muscle of the upper pharynx and esophagus causes difficulty in swallowing, choking and coughing when drinking water, and liquid flowing out of the nostrils. The involvement of the thoracic muscle and diaphragm causes shallow breathing and dyspnea. 3. Polyarteritis nodosa: A group of nodular inflammation and necrosis characterized by segmental inflammation and necrosis mainly affecting medium-sized muscular arteries and small arteries with muscle layers, with secondary ischemia in the blood supplying tissue of the involved vessels. The lesions can occur at any site, but are more common at arterial bifurcations. Nodular polyarteritis is characterized by irregular fever, headache, excessive sweating, weight loss, muscle pain, abdominal pain, and arthralgia. Neurological damage: peripheral nerve involvement accounts for about 60% of cases, manifesting as polyneuritis mononeuritis or/and polyneuritis, and peripheral neuritis. Central involvement accounts for about 40% and may manifest as diffuse or limited unilateral brain or multi-local brain and brainstem dysfunction, convulsions, impaired consciousness, cerebrovascular disease, etc. 4. Giant cell arteritis: It is a systemic necrotizing vasculitis of unknown cause. The disease almost always occurs in elderly people over 50 years of age, and the age of onset is between 50 and 90 years. The incidence is higher in women than in men. Systemic symptoms: The onset of the disease can be rapid or slow, with prodromal symptoms including malaise, poor appetite, weight loss and hypothermia. Symptoms of organ involvement: complex clinical symptoms and signs depending on the involved vessels. (1) Headache is the most common, with about half of the patients having the first symptom. It is accompanied by painful scalp tenderness or palpable painful nodules, and the scalp nodules have diagnostic value if they are distributed along the temporal artery. (2) Ocular muscle paralysis is also more common, with drooping eyelids and difficulty in upward vision, often occurring simultaneously with diplopia. Sometimes the pupil is not equal in size or Horner’s sign is present. Ocular muscle palsy may be caused by optic nerve or ocular muscle lesions, and presents with mild to severe upward gaze difficulties. (3) Intermittent dyskinesia: About 2/3 of patients have intermittent chewing discomfort and chewing pain due to facial arteritis and poor local blood supply, resulting in spasm of the mandibular muscles; sometimes dysphagia, dullness of taste, and slurred spitting due to dyskinesia of the tongue muscles. Intermittent dyskinesia may also affect the extremities, manifesting as intermittent claudication and poor mobility of the upper extremities. (4) Neurological manifestations: About 30% of patients present with multiple neurological symptoms, such as episodic cerebral ischemia, stroke, hemiparesis or cerebral thrombosis due to carotid or vertebral artery lesions. Secondary neurological manifestations due to neurovascular lesions are also diverse, such as mononeuritis, peripheral polyneuritis, peripheral neuritis of upper and lower extremities, etc. 5. Wegener’s granulomatosis: It is a kind of necrotizing granulomatous vasculitis. The lesions involve small arteries, veins and capillaries, and occasionally large arteries, mainly invading the upper and lower respiratory tracts and kidneys. It usually begins as a focal granulomatous inflammation of the nasal mucosa and lung tissue and progresses to a diffuse necrotizing granulomatous inflammation of the blood vessels. It often presents with nasal and paranasal sinusitis, pulmonary lesions, and progressive renal failure. It may also involve joints, eyes, and skin, and may invade the eyes, heart, nervous system, and ears. About 1/3 of patients develop neurological lesions during the course of the disease. Patients with peripheral neuropathy are the most common, and polyneuritis moniliformis is the main type of lesion, manifesting as symmetric peripheral neuropathy. 6. Microscopic polyangiitis: also known as microscopic polyarteritis, is a systemic, necrotizing vasculitis that primarily invades small vessels, including capillaries, small veins, or microarteries, but can also involve small and/or medium-sized arteries. The disease is more common in males, with a male to female ratio of approximately 2:1. It mostly develops at the age of 50-60 years and can invade multiple organs throughout the body, such as the kidneys, lungs, eyes, skin, joints, muscles, gastrointestinal tract, and central nervous system, with necrotizing glomerulonephritis being the prominent clinical manifestation. Non-specific symptoms such as irregular fever, fatigue, rash, arthralgia, myalgia, abdominal pain, neuritis and weight loss. About 20-25% of patients have neurological involvement, which may include polyneuritis, peripheral neuritis, central neurovascular inflammation, etc., manifesting as local peripheral sensory or motor disorders, ischemic encephalopathy, etc. 7.Dry syndrome (SS): SS is a chronic inflammatory autoimmune disease mainly involving exocrine glands. In addition to dry mouth and dry eyes due to damaged salivary glands and lacrimal glands, there are also symptoms of multi-system damage due to the involvement of other organs outside the glands. Neurological manifestations: The incidence of involvement of the nervous system is about 5%. Peripheral nerve damage is common, whether it is central or peripheral nerve damage is related to vasculitis. 8, rheumatoid arthritis: peripheral nerve damage is common, manifested as local peripheral sensory or motor disorders, mostly related to vasculitis.