Fever is one of the most common early signs of lupus. Individuals who have been diagnosed with lupus sometimes experience lupus "flares," or periods when the disease worsens; these flares can be accompanied by fever in addition to other symptoms. Lupus patients are often more susceptible to infection as well, which is usually accompanied by a fever. It also is typical for many lupus patients regularly to run temperatures that are one or two degrees above normal.
Although fever can be an early indicator of lupus, it can be difficult for an undiagnosed patient to tell the difference between a lupus fever and a run-of-the-mill fever caused by sickness. In fact, the onset of lupus can feel a lot like a typical bout of the flu—a condition referred to as "flu-like syndrome." These symptoms include muscle pain, joint pain and fatigue. To differentiate between the flu and lupus, an individual should watch for other lupus symptoms, such as weight loss or gain, hair loss, mouth sores, dry eyes, and easy bruising. A rash may also appear on the face and cover the nose and cheeks, and skin lesions or rashes typically will grow worse when exposed to sunlight.
"Normal" temperature varies from person to person, but the universal normal temperature for a healthy human being is about 98.6 degrees Fahrenheit (37 degrees Celsius). A fever is considered to be any temperature greater than 99.6 degrees Fahrenheit (about 37.5 degrees Celsius). Many patients run a chronic low-grade fever with lupus, one or two degrees above normal, unaccompanied by other usual symptoms of a lupus flare—rash, mouth sores, fatigue or muscle aches.
Since it's common for patients to run a slight fever with lupus on a regular basis, it's important for an individual to figure out what is "normal" for him by taking his temperature several times a day. A person with lupus should watch for fever any time he doesn't feel well, and should practice good hygiene to prevent infection. If a fever with lupus higher than 102 degrees Fahrenheit (about 38.9 degrees Celsius) is detected, the patient should consult with his doctor as soon as possible; high fever is one sign of infection. Other signs of infection include unusual pain, cramping, swelling, headache with neck stiffness, trouble breathing, nausea and diarrhea.
Infection can be a significant problem for individuals with lupus, as many of the medications taken by lupus patients make them more vulnerable to infection. Such medications include immunosuppressive drugs, corticosteroid, large amounts of aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs). Infections can come in many different forms, including urinary tract infection and respiratory infection. Any infection should be taken seriously, since it can result in death in lupus patients.
Regardless of the cause, lupus patients should be sure to drink plenty of fluids to prevent dehydration during a fever. While occasional or chronic low-grade fevers can be relatively harmless, any high fever with lupus should be a signal that it's time to consult with a doctor before the condition grows worse. Dehydration can signal dangerous responses in the body for lupus patients.