Pyogenic infections Meningococcus H. influenzae Pneumococcus S.aureus GAS
Pneumococcus infections in the normal host Infancy Elderly Recent viral infection Malnutrition Vitamin A deficiency „Polvere fa danno” (Leonardo da Vinci)
Pneumococcus infections in IDs B cell defects Complement deficiency Congenital asplenia Hyposplenia Neutropenia AED-ID NEMO/IB deficiency IL-1R-associated kinase-4 (IRAK-4)deficiency
Arthritis of the right hip – 2.5 yr We: 75 mm/h, CRP: 193 mg/l RBC: 3.30 T/l, Hgb: 70.0 g/l WBC: 4700 /mm3, PMNL: 2300 /mm3 Culture of hip joint fluid: S. pneumoniae, serotype 14 Treatment: ceftriaxon,12 days; clindamycin,10 days Two episodes of low-grade fewer (< 38 OC)
Meningitis – 5½ yr Moderate headache, vomitus, subfebrility We: 40 mm/hr, CRP: 8.1 mg/l 87 mg/l RBC: 4.02 T/l, Hgb: 94.0 g/l WBC: 4800 /mm3, PMNL: 56% Culture of CSF: S. pneumoniae, serotype 14 Treatment: cefotaxim, 12 days; AMX, 4 weeks Three episodes of low-grade fewer (< 38 OC) IVIG monthly
SPAD: Selective anti-Polysaccharide Antibody Deficiency Invasive disease by encapsulated bacteria Poor Ab response to polysaccharide Ag Normal levels of Ig and IgG subclasses Intact responses to protein antigens
IRAK-4 deficiency Recurrent, invasive infections caused by S. pneumoniae No characteristic findings on physical exam No developmental abnormalities such as ED Febrile and inflammatory responses are minimal or delayed
Therapy IVIG substitution AB prophylaxis Vaccination with both conjugated and non-conjugated capsular vaccines
Staphylococcus aureus Multiple strains Localizing strains Toxin-producing strains Coagulase TSST-1 Enterotoxin Exfoliation Clumping factor Protein A Toxic shock Food Scalded skin syndrome poisoning syndrome Bacteremia Focal infection Abscess Disseminated Sinusitis Infection Boil
Diagnostic criteria of Staphylococcus TSS MAJOR CRITERIA (ALL REQUIRED) Acute fever; temperature >38,80 C Hypotension (orthostatic, shock; below age-appropriate norms) Rash (erythrodema with late desquamation) MINOR CRITERIA (ANY 3) Mucous membrane inflammation Vomiting, diarrhea Liver abnormalities Renal abnormalities Muscle abnormalities Central nervous system abnormalities Thrombocytopenia EXCLUSIONARY CRITERIA Absence of another explanation Negative blood cultures (except occasionally for S. aureus)
3 - Scarlet fever
3-year-old girl Fever (38.8 C) Right periorbital edema Conjunctivitis 3x3 cm erythematous area over the right eye Intact extraocular eye movements No evidence of chemosis or proptosis Supple neck Diagnosis? Therapy?
Diagnosis Orbital osteomyelitis Orbital cellulitis Periorbital cellulitis Preseptal cellulitis
Presenting findings in periorbital cellulitis Redness (color) Swelling (rubor) Tenderness (dolor) Normal eye movements Fever Leukocytosis Chemosis Conjunctivitis Blue-purple hue (Hib)
Characteristic findings in orbital cellulitis Impairment of eye movements Pain in the eye Progress rapidly to cavernous sinus thrombosis meningitis brain abscess
The best choice of treatment Penicillin Ampicillin Cefuroxime Cefotaxime Erythromycin
Pathogens causing periorbital cellulitis S. aureus GAS H. influenzae Str. pneumoniae Gram- organisms Anaerob bacteria
Pathogenesis of periorbital cellulitis Infection due to contiguous skin infection sinusitis trauma
6-year-old boy Fever (38.8 C) for 3 days Purulent nasal discharge Bilateral otorrhea Cough Frontal headache URTI ten days ago Therapy?
The best choice of treatment i.m. ceftriaxone i.v. cefotaxime p. os cephalexin p. os erythromycin p. os amoxicillin
Bacteria causing mild or moderately severe RTI Str. pneumoniae H. influenzae M. catarrhalis S. aureus (rarely)
6-year-old girl No fever Healing varicella lesions Rapidly enlarging skin lesion 3x4 cm area erythema tenderness Gram+ cocci in clusters (Gram stain) Other lesions are scabbed and dry
The best choice of treatment penicillin G ampicillin nafcillin ceftriaxone vancomycin