Neisseria meningitidis Disease process Attach to specific receptors on non-ciliated cells of nasopharnyX Pili--mutants have decreased cell binding ability Organisms internalized into phagocytic vesicles by endocytosis After 18-24 hours, found in sub-epithelial tissue space BIOL 533 Lecture ll
BIOL 533 12 Lecture 11 Neisseria meningitidis • Disease process – Attach to specific receptors on non-ciliated cells of nasopharnyx • Pili—mutants have decreased cell binding ability – Organisms internalized into phagocytic vesicles by endocytosis • After 18-24 hours, found in sub-epithelial tissue space
Neisseria meningitidis Tissue damage Type of damage Endothelial damage Inflammation of blood vessel walls Thrombosis Disseminated intravascular coagulation Mechanism(endotoxin) Continuous production of excess membrane fragments that contain LPS BIOL 533 Lecture ll
BIOL 533 13 Lecture 11 Neisseria meningitidis • Tissue damage – Type of damage • Endothelial damage • Inflammation of blood vessel walls • Thrombosis • Disseminated intravascular coagulation – Mechanism (endotoxin) • Continuous production of excess membrane fragments that contain LPS
Neisseria meningitidis Epidemiology Transmitted by respiratory secretions to people living in close contact Incidence during Spring Susceptibility Children <5 years old Older individuals infected during epidemics Maternal ab protection for first 6 months BIOL 533 Lecture ll
BIOL 533 14 Lecture 11 Neisseria meningitidis • Epidemiology – Transmitted by respiratory secretions to people living in close contact – Incidence during Spring – Susceptibility • Children <5 years old • Older individuals infected during epidemics • Maternal Ab protection for first 6 months
Neisseria meningitidis Syndromes Meningitis Symptoms: headache and fever(young children- fever and vomiting) Mortality Untreated 100% Treated: <15% when antibiotics administered promptly Incidence of neurological problems is low BIOL 533 Lecture ll
BIOL 533 15 Lecture 11 Neisseria meningitidis • Syndromes – Meningitis • Symptoms: headache and fever (young children— fever and vomiting) • Mortality – Untreated: 100% – Treated: <15% when antibiotics administered promptly • Incidence of neurological problems is low
Neisseria meningitidis Syndromes Meningococcemia(with or without meningitis) Life-threatening, with mortality of 25%, even when promptly treated Patholog y Thrombosis of blood vessels Multiorgan involvement Small skin lesions on trunk and lower extremities(may form larger hemorrhagic lesions May progress to completely debilitating DIC with shock (destruction of adrenal gland) BIOL 533 Lecture ll
BIOL 533 16 Lecture 11 Neisseria meningitidis • Syndromes – Meningococcemia (with or without meningitis) • Life-threatening, with mortality of 25%, even when promptly treated • Pathology – Thrombosis of blood vessels – Multiorgan involvement – Small skin lesions on trunk and lower extremities (may form larger hemorrhagic lesions – May progress to completely debilitating DIC with shock (destruction of adrenal gland)