Source: Manual of Ambulatory Pediatrics 2010
SOAP Note – Cat Scratch Disease
CAT SCRATCH DISEASE
A bacterial infection that follows cutaneous inoculation by the bite or scratch of a cat, resulting in regional lymphadenopathy. Disease is generally self-limiting and resolves over time.
D. Etiology
A. Bartonella henselae, a proteobacterium
B. Cats are common reservoir for human disease.
II. Communicability
A. Generally transmitted by kittens younger than 6 months
B. No evidence of person-to-person transmission
III. Incidence
A. More common in children than adults; peak incidence between ages 5 and 14 years of age
B. Often multiple cases found within a family
C. Occurs more often in fall and winter
IV. Incubation period
A. 7 to 12 days from time of scratch to appearance of primary cutaneous lesion
B. 5 to 50 days, with a median of 12 days, from appearance of lesion to resultant lymphadenopathy
V. Subjective findings
A. Fever in 30% of patients
B. Systemic symptoms in 30% of patients: Malaise, anorexia, headache, fatigue
C. Lymphadenopathy: Most common presenting complaint
1. Node(s) enlarged, tender
2. Overlying skin warm and inflamed, indurated
D. Pertinent subjective data to obtain
1. Complete history of present illness; onset of symptoms, duration of symptoms
2. New pet in home
3. History of kitten or cat scratch or bite
4. History of bite or papule in area where it would drain to affected node(s)
5. Signs or symptoms indicative of other diseases with similar presentation (i.e., infectious mononucleosis, or of complications of cat scratch disease)
VI. Objective findings
A. Regional lymphadenopathy in an immunocompetent person
1. Involves nodes draining site of inoculation
2. Sites affected (in decreasing order of frequency): Axillary, cervical, submandibular, preauricular, epitrochlear, femoral, inguinal
3. Node(s) enlarged, tender
4. Surrounded by area of erythema, induration
5. Skin warm to touch
6. Node may suppurate spontaneously (in 30% of children)
7. Examine all nodes.
B. Elevated temperature
C. Inspect entire body for site of cat scratch or papule, which appears approximately 1 to 2 weeks before lymphadenopathy.
1. Cat scratch, scar, or bruising from healed scratch
2. Papule at site of inoculation
D. Conjunctivitis: Parinaud oculoglandular syndrome
1. Inoculation site: Conjunctiva or eyelid of eye
2. Mild to moderate conjunctivitis
3. Preauricular adenopathy
E. Complete physical exam to rule out other diagnoses or complications
1. HEENT for signs of infection
2. Abdominal exam to assess for organomegaly, masses, tenderness
3. Neurologic exam to rule out encephalopathy
4. Cardiovascular and lung exam
F. Laboratory tests
1. Indirect fluorescent antibody (IFA) for detection of antibodies to
Bartonella
a. Testing available through CDC
b. State health departments can obtain reagents through CDC.
c. Commercial laboratory results are not always reliable.
2. Serologic testing should be considered for patients with adenopathy, fever, malaise, and history of contact with kittens or cats.
VII. Assessment
A. Diagnosis is made by history and clinical findings; chronic lymphadenopathy, feline contact, inoculation site
B. Confirmed by serologic testing, particularly for patients with systemic symptoms
C. Differential diagnosis
1. Includes most causes of lymphadenopathy
2. Acute pyogenic cervical adenitis
VIII. Plan
A. Symptomatic
1. Warm compresses to node
2. Tylenol or ibuprofen for discomfort
B. Antibiotic therapy if acutely ill or markedly enlarged, tender nodes or hepatosplenomegaly; use one of the following:
1. Azithromycin: 5 mg/kg/d (loading dose 10 mg/kg) for 5 days or
2. Erythromycin: 30 to 50 mg/kg/d in four divided doses; usual dose for child over 20 kg, 250 mg, qid
or
3. Doxycycline: 100 mg every 12 hours for child over 9 years of age
IX. Education
A. Avoid rough play with kittens and cats.
B. Kittens are more likely than older cats to transmit bacteria to humans.
C. New pets should be at least 1-year-old if immunocompromised child in household
D. Fleas are major vector for transmission among cats.
E. About 40% of cats carry B. henselae at some time in their lives
F. Cats that carry B. henselae do not exhibit any signs of illness
G. Wash hands thoroughly after petting or playing with a kitten or cat. Bacteria may also be present on cat fur. It is possible to contract the disease by petting a cat and then rubbing eyes.
H. Use aggressive flea control for cats and kittens to prevent transmission between cats.
I. Immediately and thoroughly wash all cat bites and scratches.
J. Immunocompromised children should avoid contact with cats that scratch or bite.
K. Do not allow cats to lick open cuts or wounds.
L. Family pet does not have to be destroyed because disease transmission is transient.
M. Declawing can be considered.
N. Nodes may be painful for several weeks. Lymphadenopathy may persist for several months.
O. Disease is generally self-limiting.
P. Reinfection is rare.
X. Complications
A. Encephalopathy
B. Thrombocytopenia purpura
XI. Consultation/referral
A. Child with suppurative node for needle aspiration
B. Child with Parinaud’s oculoglandular syndrome
C. Immunocompromised child