Peds: Day 13

Last day of Inpatient was on Friday. I worked 6a-5p, as always, and it was a slower-than-average day. Only 1-2 new admissions in the afternoon. Another day, didn't learn anything from the residents/attending...I actually spent the afternoon working on assignments for the clerkship. Finally - Inpatient Peds is FINISHED!!!! :) :) :)


A little boy came in a few days ago with cervical lymphadenopathy (enlarged lymph node in his neck). The node was mobile, firm, and nontender. It had been there, enlarging, for a few days prior to admission. Before the node was noticed, the patient went to the dentist's office for a teeth cleaning. So we were fairly certain that the lymph node was enlarged due to the increase in oral bacteria draining in his blood and through that lymph node. So we put him on antibiotics that cover oral bacteria - anaerobes are prevalent in your mouth, so we put him on IV Clindamycin and a small amount of corticosteroid to help decrease the swollen lymph node. He did not improve after 3 days. So we went in and spoke with the mother again about other possible diagnoses, and we found out that he had played with a new kitten recently. From that new information, we decided that he most likely has "cat scratch disease", caused by the bacteria "Bartonella henselae". The antibiotic we had him on does not cover bartonella, so we had to switch him over to either doxycycline or azithromycin (we chose azithromycin). He should improve with this oral treatment, and he was discharged home after IV Clindamycin was discontinued.


A few learning points from this case:
  From physical exam, you can ascertain many details just by palpating the enlarged lymph node(s):

"Reactive" lymph nodes are usually discrete, mobile, feel rubbery, are minimally tender, and are often referred to as "shotty."

Infected lymph nodes are usually isolated, asymmetric, tender, warm, and erythematous; they may be fluctuant; they are less mobile and discrete than reactive lymph nodes.

Malignant lymph nodes often are hard, fixed or matted to the underlying structures; they are usually nontender.

  - Acute Unilateral LN — Acute unilateral cervical LN is usually caused by S. aureus or GAS. The initial treatment depends upon the severity of symptoms.     - S. aureus and GAS — Between 40 and 80 percent of cases of acute unilateral cervical lymphadenitis are caused by S. aureus or GAS. Clinical features are usually not helpful in differentiating between staphylococcal and streptococcal adenitis. Most of these infections occur in children younger than five years of age. Patients may have a history of a recent URI or impetigo. Although systemic symptoms of fever, tachycardia, and malaise may be present, the patient usually does not appear toxic. Submandibular nodes are affected in more than 50 percent of cases. The lymph node usually is 3 to 6 cm in diameter, tender, warm, erythematous, nondiscrete, and poorly mobile. One-fourth to one-third of infected nodes suppurate and become fluctuant.
     - Anaerobic bacteria — Acute unilateral cervical lymphadenitis in older children with history of periodontal disease usually is caused by an infection with anaerobic bacteria.
     - Tularemia — Tularemia is a febrile illness caused by an infection with Francisella tularensis that usually occurs following contact with infected animals (eg, rabbits, pet hamsters) or the bite of blood-sucking arthropods. The most common clinical presentation is the ulceroglandular syndrome, characterized by a papular lesion in the drainage field of the inflamed lymph node.  Most cases in the United States occur in the south-central region.
     - Tuberculosis is an uncommon cause of chronic cervical adenitis that is usually unilateral but occasionally can be bilateral. 
     - Cat scratch disease — CSD is a relatively common infection caused by inoculation of B. henselae into the skin following a cat bite or scratch. From 7 to 60 days following the scratch, the lymph node draining the site of inoculation becomes warm, tender, and slightly erythematous. There is usually (but not always) a history of contact with a cat, often a kitten, although patients and parents frequently do not recall a bite or scratch. 

Cat Scratch Disease with Lympadenopathy of the Axillary Region:

  - Acute Bilateral LN - 
    - Viral URI — Acute bilateral cervical lymphadenitis is most often caused by a benign, self-limited viral upper respiratory infection (eg, enterovirus, adenovirus, influenza virus). Patients often have a history of an ill contact and current or recent symptoms that may include sore throat, rhinorrhea, nasal congestion, and/or cough. The lymph nodes typically are small, rubbery, mobile, discrete, minimally tender, and without erythema or warmth; they are often referred to as "reactive" or "shotty" lymphadenopathy. Although the clinical course is self-limited, the lymphadenopathy may last for weeks.
     - Group A streptococcus — GAS pharyngitis is a common cause of bilateral cervical lymphadenitis, which is often tender.
     - Other causes — Acute bilateral cervical lymphadenitis also is associated with pharyngitis resulting from Mycoplasma pneumoniae and primary gingivostomatitis due to herpes simplex virus. Epstein-Barr virus (EBV) and cytomegalovirus (CMV) usually cause generalized lymphadenopathy but may present as acute bilateral cervical lymphadenitis.


**There are also much less common causes of cervical lymphadenitis, such as leukemia, lymphoma, kawasaki disease, and PFAPA syndrome. These etiologies are investigated if present with other symptoms aside from cervical lymphadenopathy, or if the lymphadenopathy does not resolve or have a likely/probable identified etiology.

Reference: www.uptodate.com