Blood work:
A complete guide for monitoring HIV

May 2007     View PDF     En español

Chemistry Screen (CHEM-25 OR SMA-25)

A chemistry panel (chem panel, chem screen) tests the levels of 25 chemicals in the blood. It can help determine if your body is working properly. (Other types test 12, 14 or 20 chemicals and are called SMA12, SMA14 and SMA20.) A chem screen should be done once a year in people not taking medications and more often in people who are. Some of the important values follow.

Sodium (Na):
The normal range is 135–145 mEq/liter.
Sodium is a part of table salt and is important for keeping the balance of fluid in your body, nervous system and muscle tissue (including the heart). Too much of it can be a symptom of being dehydrated while too little can be caused by excessive IV fluids or may indicate kidney problems. Eating salty foods will not affect your sodium level as long as you’re drinking fluids.

Potassium (K):
The normal range is 3.5–5 mEq/liter.
Potassium is mostly found inside your cells and helps to regulate nerve impulses and heart muscle. A high level may indicate kidney failure and severe injuries. A low level can occur after severe vomiting, diarrhea, long periods without food and in people on high doses of pills to reduce water retention (diuretics). Potassium is found in most foods. People who eat a fairly balanced diet will have no problem getting enough of it.

Chloride and Magnesium (Cl and Mg):
The normal range of chloride is 100–106 mEq/liter. The normal range of magnesium is 1.5–2.0 mEq/liter.
Chloride and Magnesium are two important elements in your blood. Chloride is important for controlling your body’s balance of fluid. Magnesium is involved in muscle contractions and processing protein.

Glucose:
Normal levels are 75–125mg/dl.
Glucose is sugar, and glucose values are used to check for diabetes. Some drugs may alter glucose levels, such as Pentam (IV pentamidine) or drugs that affect the pancreas. Insulin resistance is one cause of high blood glucose. Insulin resistance occurs when insulin (the hormone that moves sugar into cells) is less effective than usual in your body. This may occur with long-term use of anti-HIV drugs, from HIV itself or from both HIV and the drugs. It is treatable with medications.

Cholesterol and Triglycerides:
Normal cholesterol levels are 150–250mg/dl. Triglycerides can range from 47–175mg/dl.
Cholesterol and triglyceridesare fatty substances in the body. Their levels help measure the risk for conditions such as heart disease and wasting. Triglycerides often decrease in people with HIV, possibly due to malnutrition or wasting in advanced stages of disease. High cholesterol and triglycerides may occur among people living with HIV for many years. They can also be a side effect of anti-HIV drugs.

Amylase:
Normal levels are 25–125 milliunits/mL.
Amylase is secreted by the saliva glands as well as in the pancreas. Elevated levels may be an early sign of inflammation of the pancreas, or pancreatitis. This is a serious side effect of some common medications used to treat HIV and its conditions.

Liver Function Tests (LFTs):
LFTs include a number of lab results that help the health of the liver. These include ALT (SGPT), AST (SGOT), LDH, alkaline phosphatase and total bilirubin. Elevated liver enzymes are caused by some medications. It can also be caused by liver disease such as hepatitis B or C, injuries and tumors. Abnormal LFTs are common in 60–70% of people with HIV, but liver failure is unusual. High alkaline phosphatase levels along with normal bilirubin levels can show serious disease and are often seen in people with MAC (Mycobacterium Avium Complex), CMV (cytomegalovirus), histoplasmosis, drug side effects or KS (Kaposi’s Sarcoma). Bilirubin, a product of dead red blood cells, is removed through the liver. High bilirubin levels can be a sign of hepatitis (perhaps with a yellow skin color), bile duct obstruction and other liver problems. Some HIV drugs—specifically Reyataz (atazanavir) and Crixivan (indinavir)—can cause high bilirubin levels. However, this may not be a sign of liver problems. If a pregnant woman has high bilirubin, this can harm the unborn child

Kidney Function Tests:
Two indicators are used to assess kidney function—creatinine and BUN (blood urea nitrogen). High levels of both indicate kidney disease or being dehydrated. High uric acid levels can be a sign of kidney deficiency but may also indicate other conditions like lymphoma or inflammation. Kidney problems in people with HIV can be caused by HIV itself (HIV Associated Nephrotoxicity, HIVAN) and/or may result from drug side effects.

Proteins:
Albumin and globulin are the two main types of protein in the blood. High albumin levels indicate dehydration and low levels can signify malnutrition, liver failure or kidney disease. Globulin levels are less important.