Cat Scratch Disease

Cat Scratch Disease

Cat scratch disease is a bacterial infection brought about by a gram negative bacterium called Bartonella henselae often passed on due to a cat bite or scratch. ^[1]

Epidemiology

In the United States, 2,000 hospital cases of the disease are reported every year. Some reports show male predilection while others reveal equal predominance on both genders. Most patients are young typically 18 years old and below. ^[2]

Causes

Bartonella henselae is a small, slow-growing and aerobic organism. Domestic cats are the common reservoir. The transmission usually happens thru scratch or bite of cats, more often than not by kitten less than 12 months. Unusually, dogs and monkeys are associated in some cases. ^[2]

Signs and Symptoms

Patients frequently have lymph node swelling near the injury which can be painful and warm to touch. Other manifestations are fatigue, sore throat, anorexia, fever and headache. Skin lesions such as blister may be found at the spot of injury.  Rash may develop during the course. In unusual cases, there can be involvement of the musculoskeletal system, liver, spleen and the heart. In addition, the affected person can present with seizure, mental alterations, sensory loss and abnormal reflexes when the central nervous system is involved. ^{[2] [3]}

Diagnosis

History and physical examination leads to suspicion of the disease. The infection is actually hard to diagnose. One way for accurate diagnosis is thru serologic testing called Bartonella henselae Indirect fluorescence assay (IFA) test. A biopsy can also be done.

Treatment

Treatment depends on the severity. Those who present with mild or moderate symptoms are given only antipyretics and pain reliever since the disease spontaneously resolves. If the patient complains of tender, fluctuant lymph nodes, aspiration can be done. Antibiotics are generally not given unless the disease becomes systemic. Some of the antibiotics that can be given are azithromycin, rifampin and ciprofloxacin. Patients are instructed to have a follow up after two to four months. ^[2]

Prevention

As much as possible, avoid rough playing with cats and do not allow pets to come in contact with open wounds. Injuries such as cat scratches should be washed with soap and running water right away. ^[1] Kids must be taught gentle handling of pets. ^[2]

References:

1. http://www.cdc.gov/healthypets/diseases/catscratch.htm
2. http://emedicine.medscape.com/article/214100-overview#a0156
3. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002581/

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