What are the types of lupus erythematosus? 1. Discoid lupus erythematosus: It mainly invades the skin and is the mildest type of lupus erythematosus, which may have mild visceral damage and may transform into systemic lupus erythematosus in very few cases. 2. Subacute cutaneous lupus erythematosus: It is less common and is a special intermediate type. There are two types of skin lesions, one is the annular erythematous type and the other type is the papulosquamous type. Most cases have one of these two types of skin lesions alone, and a few can be present at the same time. 3. Deep lupus erythematosus: also known as lupus lipofuscinosis, again an intermediate type of lupus erythematosus. 4. Systemic lupus erythematosus: It is the most serious type among all types. The vast majority of patients have multi-system damage at the onset, and a few patients develop from other types of lupus erythematosus. Some patients also have other connective tissue diseases, such as scleroderma, dermatomyositis and dry syndrome, forming various overlapping syndromes. The clinical manifestations of SLE are diverse, complex and severe, mainly manifesting as fatigue, fever and weight loss. Skin and mucous membrane manifestations include butterfly erythema, subacute cutaneous lupus erythematosus, discoid erythema, photosensitivity, hair loss, oral ulcers, cutaneous vasculitis, Raynaud’s phenomenon, etc. Arthralgia, arthritis, joint deformity, myalgia and muscle weakness may be present. There are also more serious multi-system damages such as heart, respiratory system, kidney, nervous system, blood system, digestive system, etc. The lives of patients may be endangered due to lupus nephritis, lupus encephalopathy and the side effects of long-term heavy drug use. Is lupus erythematosus easy to diagnose? Discoid lupus erythematosus and subacute lupus erythematosus are mainly diagnosed based on rash characteristics and skin histopathological and immunopathological examinations to help confirm the diagnosis. The diagnosis of SLE is based on a combination of medical history, clinical manifestations and laboratory tests. Currently, the diagnostic criteria for SLE as revised by the American College of Rheumatology in 1997 are generally used. The diagnosis is confirmed when a patient has four or more of the 11 criteria, either sequentially or concurrently. Are there any other tests needed to diagnose SLE? SLE is complex and requires numerous laboratory tests to assist in the diagnosis, such as routine blood, urine, 24-hour urine protein, ANA, anti-dsDNA antibodies, anti-Sm antibodies, anti-cardiolipin antibodies, complement C3/C4, etc. Is lupus erythematosus easy to be misdiagnosed? Lupus erythematosus is easily misdiagnosed and underdiagnosed, especially when the initial systemic damage is not obvious and the facial lesions are atypical, so an experienced physician needs to diagnose and evaluate the disease in detail. In rare cases, continuous observation and regular checkups are needed to make an early diagnosis or to rule out a diagnosis.