Rashes are a symptom of many medical problems

Rashes are a symptom of many different medical problems and sometimes, they are just simply asymptomatic.  Certain genes can make people more likely to get rashes

I recently received a call from MC, an old patient of mine, about the appearance of  multiple, non-itchy red spots on her legs extending all the way up to the waistline.  She took a picture, but there was no close up view of the exact appearance of her rash for me to check. And since she is 70-something, I thought it was relatively uncommon in her age group to have such kind of a vasculitis (an inflammation of the blood vessels) that I was considering she showed me the picture. According to her, she was actually on her fifth day of not feeling very well when the said rash appeared and it was accompanied by abdominal pain.  A complete blood count with differential analysis, liver function test, coagulation test, chemistry panel, and ESR were done and they all turned out to be normal.  But her urinalysis showed dysmorphic hematuria (abnormalities in the shape of red cells in the urine) with 30 to 40 red blood cells/high power field and proteinuria of 2.29 g/ 24 hour.

First of all, having a rash is not as simple as it appears to be.  A rash is an area of irritated or swollen skin. Many rashes are itchy, red, painful, and irritated. Some rashes can also lead to blisters or patches of raw skin.  Rashes are a symptom of many different medical problems and sometimes, they are just simply asymptomatic.  Certain genes can make people more likely to get rashes. Determining the specific cause of a rash usually requires a description of the skin rash, including its shape, arrangement, distribution, duration, symptoms, and history.  All these factors are important in making the correct diagnosis. Accurate information about past treatments, successful and unsuccessful, is very important. Treatments that work may be a clue to the cause of the rash, may mask symptoms, or change the appearance, making a definite diagnosis harder. Sometimes, good quality pictures of an earlier stage of the rash may aid diagnosis.

Many different risk factors determine what rash or rashes a patient might get. A family history of eczema, frequent exposure to sick children, necessary use of immunosuppressive medications, and exposure to multiple medications all increase the risk of developing rashes.

A careful drug history, which includes over-the-counter medications, supplements, and prescription drugs such as birth control pills, is also important. The timing — when the medication was started and when it was stopped — may provide important clues as to the cause of a rash.

There are some rashes that only appear in association with pregnancy, either during pregnancy or even after the delivery of the baby. Most of these are not serious but can be very irritating.

The reported history will help characterize the duration, onset, relationship to various environmental factors, skin symptoms (such as itching and pain), and constitutional symptoms such as fever, headache, and chills. Based on the health-care provider’s initial impression of a rash, treatment may be started. The treatment may need to be modified pending various laboratory and special skin examinations.

A skin biopsy is very helpful, but for people who don’t want to have a scar, it’s difficult to impose such a procedure.

I was thinking of a rash of a vasculitis, particularly that of Henoch Schonlein Purpura (HSP).  Generally, HSP has a self-limited course.  Its main clinical manifestations (as shown in an article from the 1990 College of Rheumatology) can be seen in the skin as palpable purpura occurring in 100 per cent of cases; joint manifestation (arthritis), 40 per cent; bowel angina (abdominal pain after eating that occurs in individuals with on-going poor blood supply to their small intestines known as chronic mesenteric ischemia. The word angina refers to angina pectoris, a similar symptom due to obstruction of the coronary artery), 80 per cent; hematuria (blood in urine), 80 per cent; proteinuria (the presence of abnormal quantities of protein in the urine, which may indicate damage to the kidneys), 60 per cent; renal insufficiency (kidney failure), 40 per cent; and gastrointestinal bleeding, 20 per cent.  Less frequently, other organs and/or systems, such as the lungs, the central nervous system (brain & spinal cord), and the genitourinary tract, can be affected.

Although the cause of the disease is unknown, multiple infectious agents have been suggested to be responsible.  A variety of disorders have been associated with HSP, including infection with Helicobacter pylori, hepatitis B, recurrent tonsillitis, pharyngitis, and certain malignancies.  In adults (as opposed to children), renal involvement and the possibility of progression to kidney failure are greater.

HSP primarily affects children (over 90 per cent of cases).  The occurrence in adults has been rarely reported.  In children, the disorder is often self-limiting, while a more complicated course has been described in adults, including a high incidence of renal insufficiency developing in almost 40 to 50 per cent of those patients over 20 years old with bloody stools, relapsing disease, and persistent eruption which are more likely to progress to complications and may result in considerable morbidity and mortality in some patients.

Source: The Philippines Star