Cat Scratch Fever

1. Cat Scratch Fever Casey Coon FNP-S September 11th, 2013

2. Definition • Cat scratch fever (Cat Scratch disease,CSD) is a bacterial disease caused by Bartonella henselae. • Caused when a person is scratched or bitten by an infected cat and developed an infection at the site of injury. • Can also be caused when an infected cat’s saliva comes into contact with broken skin or the white of the eye (US National Library of Medicine, 2012).

3. Pathophysiology • Usually children are diagnosed, but adults may contract the disease as well • Common symptoms: • Papule or pustule at site of infection • Fatigue and fever (can be cause of FUO) • Headache • Lymphadenopathy (unilateral) on affected side nearest exposure • Overall malaise (US National Library of Medicine, 2012). Figure 1. Cat Scratch Disease. (nlm.nih.gov, 2013).

4. Etiology • Caused by an infected cat or kitten (kittens are more likely to be infected and more likely to spread infection) • Cats are infected with the Bartonella henselae bacteria which is gram negative. • Can be spread between cats by fleas • Approximately 50 percent of cats harbor B. henselae and are entirely asymptomatic (Klotz, Ianas, & Elliott, 2011).

5. Incidence • Has been described in all areas of North America and world-wide • In northern temperate zones, occurs more often August-October in warm, humid zones. • There is estimated 22,000 new cases diagnosed each year in the U.S. (Klotz, Ianas, & Elliott, 2011).

6. Screening/Risk Factors • Any person who owns cats is at risk • People with kittens (especially if they have fleas) are at increased risk Figure 2. Lymphadenopathy. (Lieberman, 2009).

7. Clinical Findings • Tender regional adenopathy (with hx of exposure to cats)- symptom in 85-90% of PT • Vesicle at inoculation site • Aching, malaise, anorexia • FEVER • Myalgia, arthralgia and arthritis • Hepatosplenomegaly (US National Library of Medicine, 2012).

8. Differential Diagnosis • Cytomegalovirus lymphadenopathy • Epstein-Barr virus lymphadenopathy • Group A streptococcal adenitis • HIV lymphadenopathy • Nontuberculous mycobacterial lymphadenitis • Staphylococcus aureus adenitis • Toxoplasmosis lymphadenopathy • Malignancy- lymphoma, leukemia (Klotz, Ianas, & Elliott, 2011).

9. Social/Environmental Considerations • Cannot be spread person to person • Can be spread from cat to cat through fleas • Is usually spread in the autumn and winter, when there is more time for contact with cats • Has been found world-wide, including U.S. (University of Rochester Medical Center, 2013).

10. Laboratory Tests • CBC, Sedimentation rate, Bartonella antibody testing, polymerase chain reaction amplification (PCR), and skin tissue sampling(Magno & Spatar, 2009). • If CSD is suspected, a serologic blood test should be performed- Bartonella henselae immunofluorescence assay (IFA) • Occasionally, a lymph node biopsy is completed in patient’s who lymph nodes do not involute, or if the diagnosis is uncertain (Klotz, Ianas, & Elliott, 2011).

11. Management/Treatment Guidelines • Non-Pharmacological- • Monitor for 2-8 weeks • Medical treatment not usually needed • Treat symptoms • Pharmacologic- • Medications to treat symptoms • Tylenol, Ibuprofen • Antibiotics including: • Azithromycin, ciprofloxacin or sulfamethoxazole (Klotz, Ianas, & Elliott, 2011).

12. Complications • Encephalopathy • Neuroretinitis • Osteomyelitis • Endocarditis • Spleen/hepatomegaly (Magno & Spatar, 2009).

13. Follow-Up • CSD usually subsides in 2-4 weeks, so follow-up in 1 month would be appropriate for patients with normal immune function • For patients who are immunocompromised, CSD can last 6-12 weeks, so monthly follow-up would be appropriate for them as well. (Magno & Spatar, 2009).

14. Counseling/Education • Avoid contact with cats if possible • If you own a cat, wash your hands thoroughly after playing with the cat • Avoid being scratched or bitten by a cat • Avoid cat saliva to reduce your chances of infection • If you have had contact with a cat and develop swollen lymph nodes, see your PCP • Avoid stray cats (U.S. National Library of Medicine, 2012).

15. Consultation/Referral • If complications arise, may need to see a specialist • Ophthalmologist • Cardiologist • Surgeon • Neurologist

16. Questions • What is the cause of cat scratch disease? • A. Staph Aureus • B. Clostridium Difficile • C. Bartonella henselae • How do you get cat scratch fever? • A. From not washing your hands after using the toilet • B. From a cat scratch or bite • C. From another person’s sneeze or cough • Who is at risk for cat scratch fever? • A. Anyone who has contact with cats • B. Children • C. Adults

17. Questions • What are some symptoms of cat scratch fever? • A. Sneezing, coughing, headache • B. Fever, malaise, lymphadenopathy • C. Abdominal pain, nausea, vomiting • As a PCP, what would you look for when you suspect cat scratch fever? • A. History of having contact with a cat and swollen lymph nodes • B. Travel out of the country and diarrhea • C. Family history of the disease • What are some complications of cat scratch fever? • A. Sepsis • B. Pulmonary Emboli • C. Encephalopathy

18. Questions • How would you treat cat scratch fever? • A. Chelation therapy • B. Antibiotics • C. Radiation therapy • How long does cat scratch fever usually last? • A. 2-4 weeks • B. 5-7 days • C. 3-6 months • How can you prevent cat scratch disease? • A. Get a vaccine • B. Wear long pants when walking through the woods • C. Avoid contact with cats

19. Last one! • What are some differential diagnosis for cat scratch disease? • A. Pneumonia • B. Epstein-Barr virus lymphadenopathy • C. Rhabdomyolysis

20. References