Purple patches on face

It is not surprising to have pimples on the face, but it is easy to worry if spots appear on the face. On the one hand, spots are very obvious on the face and have a great impact on the image. On the other hand, the sudden appearance of spots will make people worry about the existence of certain diseases. Be careful if you have purple patches on your face, as they may be caused by diseases such as allergic purpura, systemic lupus erythematosus, dermatomyositis, etc. Find out the cause as soon as possible and solve it accordingly.

Henoch-Schonlein purpura

Most cases present with skin purpura as the first symptom. Skin lesions appear as pinpoint to soybean-sized petechiae, ecchymoses or urticaria-like rashes or pink maculopapular rashes that do not fade when pressed, which is purpura. Purpura may merge into patches and eventually turn brown. It usually disappears within 1 to 2 weeks without leaving any trace. In severe cases, blisters, blood blisters, necrosis and even ulcers may occur. The rash often occurs in weight-bearing areas, especially on the extensor side of the limbs, especially the lower limbs, around the ankle joints and buttocks. The lesions are symmetrically distributed, appear in batches, and are prone to recurrence. Purpura alone is called simple purpura.

Systemic lupus erythematosus

The manifestations are varied and can be roughly divided into two categories: specific and nonspecific. ① Specific skin lesions include butterfly rash, subacute cutaneous lupus erythematosus, and discoid erythema. ② Non-specific skin lesions include photosensitivity, hair loss, oral ulcers, cutaneous vasculitis (purpura), pigmentation changes (deposition or loss), livedo reticularis, Raynaud's phenomenon, urticarial rash, and rarely, lupus panniculitis or deep lupus and bullous lupus erythematosus.

Dermatomyositis

In 55% of patients, the rash appeared before myositis, in 25% it occurred simultaneously with myositis, and in 15% it appeared after myositis. The type and extent of the rash may vary from person to person, and the rash may also vary in the same patient at different stages of the disease. In some patients, the rash and weakness may go hand in hand, whereas in others, the rash and weakness may be unrelated.

Dermatomyositis has a variety of cutaneous manifestations. Among them, the most specific for diagnosis is Gottron's maculopapular rash or Gottron's sign. It is common in the metacarpophalangeal joints, interphalangeal joints, elbows, knees and other joint extensor surfaces, as well as shoulders, hips and other areas prone to friction. Characteristic rashes include: ① Dark purple-red rash on the eyelids, especially the upper eyelids, which may be on one or both sides, often accompanied by periorbital edema and capillary dilation near the eyelid margin. When edema is severe, the double eyelids cover the eyes and vision is impossible. This purple-red rash may also appear on the forehead, cheekbones, bridge of nose, nasolabial grooves, front of neck, upper chest (V-shaped distribution), back of neck, upper back, shoulders and outer sides of upper arms (shawl-like distribution). ② "Technician's hand"-like changes: keratinization, thickening, and cracking of the skin on the finger pads. The palms, soles, trunk, and limbs may also have hyperkeratosis with follicular keratosis; dirty, dark horizontal streaks appear on the palmar and lateral surfaces of the fingers. Because the changes are similar to those in the hands of manual laborers, it is called "technician's hands". Other skin and mucous membrane changes: Red atrophic plaques with scales may appear on the scalp, which are often misdiagnosed as psoriasis or seborrheic dermatitis; periungual capillary dilation, or spots may appear. Photosensitivity, pruritus, panniculitis, cutaneous mucin deposition, leukoplakia, multifocal lipoatrophy, and Raynaud phenomenon have also been reported.

Thrombocytopenic purpura

Clinical manifestations

The acute form is common in children. The onset is acute, and in a few cases it presents as an explosive onset. There may be mild fever, chills, sudden onset of widespread skin and mucous membrane purpura, and even large ecchymosis. Skin petechiae are mostly systemic, more common on the lower limbs, and evenly distributed. Mucosal bleeding is common in the nasal cavity and gums, and blood blisters may occur in the mouth.

The chronic type is common in young women, with an insidious onset and mild symptoms. Bleeding often occurs repeatedly, and each episode may last from days to months. Skin purpura, ecchymosis, and petechiae are often seen in the distal parts of the lower limbs or below the tourniquet. There may be bleeding from the nose, gums, and oral mucosa, and menorrhagia is sometimes the only symptom in women.