Cat Scratch Disease - Symptoms 

Most people with cat scratch disease remember being around a cat, but often cannot recall receiving a scratch or a bite. A blister or a small bump develops several days after the scratch or bite and may be mistaken for a bug bite. This blister or bump is called an inoculation lesion (a wound at the site where the bacteria enter the body), and it is most commonly found on the arms and hands, head, or scalp. These lesions are generally not painful.

Usually within a couple of weeks of a scratch or bite, one or more lymph nodes close to the area of the inoculation lesion will swell and become tender. (Lymph nodes are round or oval-shaped organs of the immune system that are often called glands.) For example, if the inoculation lesion is on the arm, the lymph nodes in the elbow or armpit will swell.

These swollen lymph nodes appear most often in the underarm or neck areas, although if the inoculation lesion is on the leg, the nodes in the groin will be affected. They range in size from about ½ inch to 2 inches in diameter and may be surrounded by a larger area of swelling under the skin. The skin over these swollen lymph nodes can become warm and red, and occasionally the lymph nodes drain pus.

In most kids, swollen lymph nodes are the main symptom of the disease and the illness often is mild. If people have other general symptoms, they might include fever (usually less than 101° F or 38.3° C ), fatigue, loss of appetite, headache, rash, sore throat, and an overall ill feeling.

Atypical cases do occur, but are uncommon. In such cases, someone might have infections of the liver, spleen, bones, joints, or lungs, or a lingering high fever without other symptoms. Some get an eye infection (Parinaud oculoglandular syndrome), with symptoms including a small sore on the conjunctiva (the membrane lining the eye or inner eyelid), redness of the eye, and swollen lymph nodes in front of the ear. Others may develop inflammation of the brain or seizures, although this is rare. All of these complications of cat scratch disease usually resolve without any lasting illness.