Neisseria Presentation PDF

Neisseria Dr. NAWAID HUSSAIN KHAN, Ph.D. ASSISTANT PROFESSOR DEPARTMENT OF MICROBIOLOGY & MOLECULAR MEDICINE ALA-TOO INTERNATIONAL UNIVERSITY Introduction: The Neisseria are gram-negative diplococci( cocci arranged in pairs) Fastidiou...

Neisseria Dr. NAWAID HUSSAIN KHAN, Ph.D. ASSISTANT PROFESSOR DEPARTMENT OF MICROBIOLOGY & MOLECULAR MEDICINE ALA-TOO INTERNATIONAL UNIVERSITY Introduction: The Neisseria are gram-negative diplococci( cocci arranged in pairs) Fastidious growth requirements Intracellular presences in polymorphs cells of infected patients. Two important Pathogens: N. Meningitidis(Meningococcus) causes meningitis/cerebrospinal fever N. Gonorrhoeae(Gonococcus) causes venereal disease gonorrhoea (STD)/Virginal discharge  Neisseria Meningitides  Biochemical properties: Oxidase- General Gram-negative, bean-shaped, positive; glucose and maltose diplococci fermenter, no beta lactamases. characteristic Cultural characteristics: s: Do not possess flagella or spores Capsulated and possess pili. Can grow in blood agar, Chocolate agar. Strict pathogenic, do not survive long outside of the host Growth is improved by addition of blood or serum. Aerobic Growth is also improved by incubation in the presence of 2- 8%CO2 Oxidative metabolism Growth temperature is 36-39⁰C and pH Produce catalase and oxidase ranges of 6-8. Colonies are 1-2 mm in diameter, Pathogenic species require convex, grey and transparent. enriched complex media and CO2 0.8 x 0.6 μm in diameter. No hemolysis in blood agar. Antige Capsular polysaccharide: Pathogene Humans are the only ns and antiphagocytic properties, on the sis: natural hosts basis of capsule polysaccharide virulen classified in to 13 serotypes. ce Among that 6 serotype are most factors commonly isolate (A, B, C, X, Y, The organisms are : W135). transmitted by airborne droplets Outer membrane protein (OMP). Colonize the nasopharynx and Lipopolysaccharide(LPS): become transient flora of responsible for endothelial injury It the upper respiratory induces septic shock by causing tract. release of cytokines. From the nasopharynx, IgA protease: It cleaves the IgA the organism can enter antibodies present in respiratory the bloodstream and mucosa. spread to meninges and grow in the cerebrospinal fluid Clinical Asymptomatic colonization is the Pyogenic meningitis: Manifestatio most common presentation. commonly seen in 3 to 5 ns: years children. Rashes developed in > 80% of case. Chronic meningococcemia: rarely occurs and characterized by petechial Septicemia can cause endothelial rash, fever, arthritis and injury due to endotoxin. splenomegaly. Post meningococcal reactive disease: Due to Waterhouse-Friderichsen syndrome: it is a severe form of fulminant immune complex develop 4 meningococcemia, characterized by to 10 days later, lead to large purpuric rashes, shock, DIC, manifestations like Arthritis, bilateral adrenal hemorrhage and rash, iritis, pericarditis, multi-organ failure. polyserositis and fever. Epidemiolo Globally each year 500000 case Outbreaks of meningitis are of meningococcal disease are most common in winter and gy: early spring, and favored by occurring with 10% of mortality. close contact between individuals like Schools, The sub-Saharan belt of Africa is military and refugee camps most prevalent area. also Hajj pilgrims. Meningitis is common in early childhood( 3months to 5 years). Serotypes distribution varies among region: Group A causes epidemic now reduced due to vaccination, Groups B and C are currently the major serotype Risk factors: C5-C9 causing invasive disease complement component Serotype worldwide.Group W( W135), was deficiency, Eculizumab responsible for 2000 Hajj therapy( complement pilgrimage outbreak. inhibiters), Hypogammaglobulinemia and hypersplenism. Laboratory Specimen: CSF, blood for case Biochemical and nasopharyngeal swab for identification: oxidase diagnosis: carrier. and catalase positive, ferment glucose and maltose but not sucrose. CSF examination: capsule Ag Serotyping by latex detection, biochemical analysis- agglutination test. CSF pressure increased, protein also increased and glucose level is decreased. On gram stain of CSF : pus cells Serology Ab to capsule with gram-negative diplococci, Ag (ELISA). lens-shaped and present. Culture on blood and chocolate Molecular diagnosis by agar: Colonies are 1-2 mm in multiplex PCR diameter, convex, grey and transparent, No hemolysis Treatmen DOC for treatments: Ceftriaxone Conjugated vaccine or Cefotaxime for 7 days. available for young t and and children. Preventio n: Vaccine: Meningococcal polysaccharide vaccine available as bivalent (groups A and C) or quadrivalent (serogroups A,C, Y, Vaccine for group B W135), 95% efficacy and duration (MenB vaccine ) a type of protection last for 3 to 5 years. of recombinant vaccine The capsule vaccine against are recently approved. serogroups B is not available because its capsule is made by sialic acid that is less immunogenic.  Neisseria Gonorrhoeae N. Non-capsulated, Outer membrane proteins(OMP): Gonorrhoeae: gram-negative kidney porin( protein I) they form shaped diplococci. membrane channel(pores). Causative agent of Opacity-associated gonorrhoea, neonatal portions(portion II): helps in conjunctivitis (ophthalmia adhesion and invasion. neonatorum) and pelvic inflammatory disease (PID). Lipooligoysaccharide (LOS) (a Antigens Pili or fimbriae: most modified form of LPS). and important virulence virulence factors, Piliated factors: gonococci are usually virulent, whereas non IgA protease: The main host piliated strains are defenses against gonococci are avirulent, that help in antibodies (IgA and IgG), complement, and neutrophils, adhesion and inhibit IgA protease degrades IgA phagocytosis. antibodies Clinical Gonorrhea is a venereal disease reported Infection may be Manifestatio since ancients. spread to periurethral ns: tissue causing abscess with sinus formation( known as Water-can perineum). In male: Acute urethritis is most common. Purulent urethral discharge ( the word gonorrhea is derived from flow of seed resembling semen). Incubation period: 2 to 7 days. Complications: Epididymitis, prostatitis, edema of the penis and balanitis. Clinical Mucopurulent cervicitis most Fitz-Hugh-Cutis Manifestatio common presentation. ns: In syndrome: its rare females. and characterized by peritonitis and associated Vulvovaginitis seen in prepubertal perihepatitis. girls and postmenopausal woman, In both Anorectal in adult females not seen because gonorrhoea. adult vagina is resistant to sexes: gonococcal infection( due to its low pH and thick stratified squamous epithelium. Pharyngeal gonorrhoea Salpingitis and pelvic inflammatory (spared by disease may lead to sterility. orogenital sex). Ocular gonorrhea. Clinical Ophthalmia Disseminate DGI characterized by Manifestatio neonatorum. d polyarthritis and ns: In gonococcal rarely dermatitis and infection(DG neonates. I): endocarditis. Characterized by Menstruation and purulent eye complement (C5-C9) discharge occurs deficiency are risk within 2 to 5 days of factor of DGI. birth. Transmission occurs In HIV infected: enhances the during birth from transmission of HIV colonized maternal genital flora. Treatment: silver nitrate solution into the eye of newborn (crede’s method).  Culture media: Laborato Sample: Male- urethral discharge, Female- endocervical chocolate agar ry swab, DGI- blood and synovial fluid culture. and Mueller- Hinton agar are diagnosi used. s: Transport media: Charcoal impregnated swabs/ stuart medium. Selective Media: Thayer martin media, Modified Gram stain: gram negative New York city diplococci, kidney shaped, more medium, Martin sensitive(90%) in urethral Lewis media are discharge in male but in female less sensitive (55%) due to the used. presence of commensal Neisseria Treatmen DOC: single dose regimen of ceftriaxone and cefixime. ts: Treat both the sex partner. Most stains are resistance to penicillin due to production of penicillinase such stains are called as PPNG strain. At present third-generation of cephalosporins are the drugs of choice, some strains shows reduced susceptibility to ceftriaxone and cefixime.