Yes, one of the down sides of Imuran is that the immune system may be suppressed too much, which can cause an increased susceptibility to infection, particularly shingles (a painful, blistering skin condition) and pneumonia.
First, let me explain shingles, then I will give you an explanation of Lupus rashes. Perhaps you and your doctor can then differentiate which one you are suffering from:
SHINGLES: Shingles (herpes zoster) is an outbreak of rash or blisters on the skin that is caused by the same virus that causes chickenpox. The first sign of shingles is often burning or tingling pain, or sometimes numbness or itch, in one particular location on only one side of the body. After several days or a week, a rash of fluid-filled blisters, similar to chickenpox, appears in one area on one side of the body. rash may affect any part of the body, including head and limbs. It may thus appear as a band around one side of the chest or abdomen, or down an arm or leg. It may affect the head, and when it affects the upper cheek or the side of the forehead it may also affect the eye (If it is shingles, you should certainly see your doctor if you have shingles affecting the side of the head, and especially if it seems to affect the tip of your nose or the eye itself). It is usually a very painful rash, and typically people can't bear clothes touching the affected area. The blisters burst and crust over, usually within a week and the area slowly settles, sometimes leaving pale scars. The pain may settle as quickly as the rash, but unfortunately some people are left with pain affecting that area for many months or even years (Post herpetic neuralgia). Most people are surprised by how ill they feel with shingles. This seems out of proportion with the extent of the skin involved. There is serious fatigue and exhaustion, sometimes with aches and pains and sometimes a mild fever. Depression is often a feature of shingles.
LUPUS RASHES: The classic Lupus rash is red or purplish and mildly scaly, appearing on the face (butterfly or malar rash) and symmetrically on the arms, fingers, or legs. This is known as Acute Cutaneous Lupus. However, there are many different types of rashes in SLE. Discoid lupus has red skin patches on the skin and scaliness that can lead to scarring. It usually occurs on the face and scalp and can lead to loss of scalp hair (alopecia).
Subacute Cutaneous Lupus Erythematosus lesions may be localized or generalized. The rash usually occurs after sun exposure and can leave a discolored spot on the skin, the lesions are usually inflammed and itchy. It may involve any place on the body, and because the erythematosus lesions may involve the palms and soles, they resemble a drug reaction. The great majority of these lesions heal without scarring, however, persistent lesions that become crusty and may heal with only slight damage of the skin.
Chronic Cutaneous Lupus Erythematosus involves the face, scalp and ears, but it may occur anywhere. The rash may be inflammed and itchy. The lesions, at the beginning, are erythematous (red), slightly elevated papules or plaques, that in time become raised, bright red and fluid-filled. Later on, the center becomes depressed, the color fades, while the fluid-filled red periphery slowly enlarges and becomes irregular with some dark red blotches. Later on, the lesions heal with a scar, leaving a white area. In the lesion involving the scalp where the lesions are red and scaly, the hair usually grows back, but if the lesion heals with scarring the hair loss in that area is usually permanent.
Lupus Panniculitis, appears as deep nodules. The lesion is situated below the skin in the subcutaneous tissue, and heals with a deep skin damage/wasting of the involved area.
Bullous Lupus Erythematosus is characterized by the presence of blisters which contain a clear seurous fluid. The rash usually appears in sun exposed areas, and only rarely is associated with burning sensation, mild dark red blotches or redness.
I hope this has been helpful to you!
Peace and Blessings