C2 deficiency

1
C2 deficiency

• Sharon E. Leonard, MD
• Nemours Childrens Clinic
• Jacksonville, FL

2
HPI

• 4 yo Hispanic male
• Recurrent pneumonia since 18 mo
• 18 mo PICU adenoviral pneumonia
• 6 additional hospitalizations for fever, wheezing
  and pneumonia
• Treated in OP setting on multiple occasions for
  wheezing, prolonged cold and fever

3
HPI

• Seen in the PCPs office on multiple occasions for
  wheezing, prolonged cold and fever.
• Diagnosed with asthma
• Treated with asthma meds and antibiotics
• No wheezing before 18 mo and no wheezing in
  between episodes
• No day time/night time/exercise induced cough.

4
PMHx, SocHx, FamHx

• Infectious history 2 OM/year, no sinusitis
• 2006 ID of retropharyngeal abscess (H.
  influenza)
• Immunizations UTD
• Developmentally normal
• Meds Flovent 44mg 2 puffs bid, alb prn
• Resides in Jax, FL with Mom and Dad. Attends
  daycare. No pets. City water. 2nd hand smoke
  exposure.
• M. gma with asthma and seasonal allergies
• Other ROS neg for constitutional, CV, GI, derm,
  rheum or neuromuscular symptoms

5
PE

• Wt 14.9 kg (25), Ht 0.965 m (5-10)
• Normal exam

6
Ancillary studies

• Multiple blood cultures 2005-07 during febrile
  illnesses associated with wheezing negative
• Superficial wound culture 2005 C. albicans
• Series of CXRs from Mar 2005 Nov 2007
• CT chest with angio May 2007
• Persistent LLL opacity with normal vessels
• Bronchoscopy May 2007
• Mild narrowing of subsegmental airways in LLL
  with increase mucopurulent secretions. BAL
  culture neg.
• Sinus x-ray normal x 2 Nov 2007

7
CXR
May 2005
Mar 2007
April 2008
8
Immune evaluation

• CBC WBC 7700, ALC 2934, ANC 3996
• Total IgA,G,M nml
• IgG subclass elevated IgG3
• Specific Ab titers pneumo 4/14, H. influ, dip,
  tet protective
• CH 50 22 U/ml (31-66)
• C2 lt1.3 mg/dl (1.6-3.5)
• C3, C4, C5, C9 fxn normal
• Sweat chloride nml

9
Treatment plan

• Pneumovax and Menactra given
• Post-pneumococcal titers (13/14 protective)
• Prophylactic antibiotics (rotating schedule of
  amoxil, bactrim and biaxin every 4 mo)
• Surgical consultation if pneumonia continues to
  recur.

10
Follow-up

• Fewer febrile illnesses
• One OM and one febrile illness.
• Treated with antibiotics twice
• No hospitalizations

11
C2 deficiency

• Most common inherited complement deficiency
  occurring in 110,000 whites.
• Variable clinical manifestations Asymptomatic to
  rheumatic disease to increased susceptibility to
  infections.
• 50 have increased susceptibility to infections.
• Caused by encapsulated organisms (S.pneumo, H.
  influenza, meningococcus).
• 25 develop SLE and discoid lupus. Other
  rheumatologic diseases include glomerulonephritis,
  anaphylactoid purpura, and vasculitis.
• Typical lab findings
• Undetectable C2 level
• Elevated IgG3
• Normal B cell and T cell studies