H.influenza

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H.influenza

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HAEMOPHILUS INFLUENZAE:

HAEMOPHILUS INFLUENZAE Dr.T.V.Rao MD Dr.T.V.Rao MD 1

PowerPoint Presentation:

Scientific classification Kingdom: Bacteria Phylum: Proteobacteria Class:Gamma Proteobacteria Order:Pasteurellales Family:Pasteurellaceae Genus:Haemophilus Species:H. influenzae Binomial name Haemophilus influenzae Dr.T.V.Rao MD 2

History:

History Pfeiffer 1892 Mistaken as causative of Human Influenza Isolated by Smith, Andrewes and Laidlaw in 1933 Need one or both of Accessory growth factors X and V present in the Blood Dr.T.V.Rao MD 3

Overview- Haemophilus:

Overview- Haemophilus Small Non-motile Gram-negative rods Transmitted via respiratory droplets, or direct contact with contaminated secretions Normal flora of the human respiratory tract and oral cavity. Dr.T.V.Rao MD 4

Haemophilus species of clinical importance:

Haemophilus species of clinical importance 1. H. influenzae - type b is an important human pathogen 2. H. ducreyi - sexually transmitted pathogen (chancroid) 3. Other Haemophilus are normal flora - H. parainfluenzae – pneumonia & endocarditis - H. aphrophilus – pneumonia & endocarditis - H. aegyptius – pink eye (purulent conjunctivitis) Dr.T.V.Rao MD 5

Haemophilus Influenza:

Aerobic gram-negative bacteria Polysaccharide capsule Six different serotypes (a-f) of polysaccharide capsule 95% of invasive disease caused by type b (Hib) Haemophilus Influenza Dr.T.V.Rao MD 6

Genus Haemophilus:

Genus Haemophilus Small, Non motile, Non sporing Oxidase test positive Pleomorphic Gram Negative Dr.T.V.Rao MD 7

Haemophilus Influenza (Pfeiffer Bacillus ):

Haemophilus Influenza (Pfeiffer Bacillus ) The size is 3 x 0.3 microns Gram negative Non Motile Non sporing Pleomorphic Appear as clusters or Coccobacillary forms in infected CSF When isolated capsulated Stained with Loffler's methylene blue Dr.T.V.Rao MD 8

Microscopic Appearance by Gram staining:

Microscopic Appearance by Gram staining Dr.T.V.Rao MD 9

Haemophilus influenza:

Haemophilus influenza Dr.T.V.Rao MD 10

Haemophilus Species:

Haemophilus Species Haemophilus species require hemoglobin for growth: X-factor ( hemin): Heat-stable substance V-factor (NAD): Heat- labile, coenzyme I, nicotinamide adenine dinucleotide, found in blood or secreted by certain organisms H. influenzae satellitism around and between the large, white, hemolytic staphylococci

Haemophilus Influenzae:

Mode of Transmission: Droplet infection and discharge from the upper respiratory tract during the infectious period. Incubation Period Unknown, probably short, 2-4 days. Infectious Period - As long as the organism is present, even in the absence of nasal discharge. - Noninfectious within 24 to 48 hours after the start of effective antibiotics. Haemophilus Influenzae Dr.T.V.Rao MD 12

Cultural Characteristics:

Cultural Characteristics Fastidious growth requirements Factors X and V are essential for growth X is Hemin heat stable Porphyrins for synthesis of Cytochromes V factor Coenzyme Nicotinamide adenine dinucleotide or NAD phosphate acts as hydrogen acceptor Aerobic 37 0 c Grows in Blood agar Dr.T.V.Rao MD 13

H. influenzae on a blood agar plate.:

H . influenzae on a blood agar plate. H. influenza, in a Gram stain of a sputum sample, appear as Gram-negative coccobacilli. Haemophilus influenza requires X and V factors for growth. In this culture Haemophilus has only grown around the paper disc that has been impregnated with X and V factors. There is no bacterial growth around the discs that only contain either X or V factor. Dr.T.V.Rao MD 14

Satellitisim:

Satellitisim When Staph aureus is streaked across plate of Blood agar with a species containing H Influenza the colonies which are large develop along the streak of Staphylococcus and small further away Dr.T.V.Rao MD 15

Biochemical Characters:

Biochemical Characters Glucose + Xylose + Lactose – Sucrose – Mannitol – Nitrites reduced Indole differs on B type causes Meningitis Dr.T.V.Rao MD 16

Resistance:

Resistance Heating at 55 0 c for 30mt destroys Drying and Disinfectants destroy Dr.T.V.Rao MD 17

Antigenic Properties:

Antigenic Properties Contains 3 Major surface antigens 1 Capsular polysaccharide 2 Outer membrane proteins (OMP) 3 Lipopolysaccharides ( LPS ) Dr.T.V.Rao MD 18

Pittman Classification:

Pittman Classification The major antigenic determinant of capsulated strains into six capsular types type a to f Typing by agglutination Quelling reactions precipitation and co agglutination or ELISA 95% of H, Influenza isolates belong to type b Dr.T.V.Rao MD 19

Type b characteristics:

Type b characteristics Has unique characters contains Pentose sugars Ribose Ribitol, instead of Hexose in others and hexosamines The capsular polyribosyl ribitol phosphate ( PRP ) of Hib induces IgG IgM and IgA antibodies –Bactericidal and opsonic and protective. So Hib PRP employed for Immunization Dr.T.V.Rao MD 20

PowerPoint Presentation:

Haemophilus influenzae type b Clinical Features* *prevaccination era Dr.T.V.Rao MD 21

Non typable Strains:

Non typable Strains H Influenza lacking capsule are non typable are most relevant in clinical infections Outer membrane proteins OMP of Hib are classified into 13 subtypes H Influenza lipo polysaccharides are more complex Genome of the organism is sequenced Dr.T.V.Rao MD 22

Pathogenicity :

Pathogenicity A Human pathogen Can produce invasive and Non invasive lesions Prominent organism in producing Meningitis Can produce laryngoepiglottitis,Conjuctivitis,Bactereima Pneumonia, Arthritis Endocarditis, Pericarditis Dr.T.V.Rao MD 23

Most strains are opportunistic Pathogens :

Most strains are opportunistic Pathogens Most strains of H. influenza are opportunistic pathogens; that is, they usually live in their host without causing disease, but cause problems only when other factors (such as a viral infection or reduced immune function) create an opportunity. Dr.T.V.Rao MD 24

Most Important Clinical Illness associated with H influenzae:

Most Important Clinical Illness associated with H influenzae Dr.T.V.Rao MD 25

Clinical Presentation:

Pneumonia: Severe shortness of breath, rapid heart rate, fever, cough and evidence of pneumonia by chest radiograph. Septic Arthritis: Swelling, warmth, pain with movement and decreased mobility of a single large weight-bearing joint. Clinical Presentation Dr.T.V.Rao MD 26

PowerPoint Presentation:

Dr.T.V.Rao MD 27

Haemophilus Influenza:

Mode of Transmission: Droplet infection and discharge from the upper respiratory tract during the infectious period. Incubation Period Unknown, probably short, 2-4 days. Infectious Period - As long as the organism is present, even in the absence of nasal discharge. - Noninfectious within 24 to 48 hours after the start of effective antibiotics. Haemophilus Influenza Dr.T.V.Rao MD 28

Haemophilus influenza type b Meningitis:

Haemophilus influenza type b Meningitis Accounted for approximately 50%-65% of cases in the prevaccine era Hearing impairment or neurologic sequelae in 15%-30% Case-fatality rate 2%-5% despite of effective antimicrobial therapy Dr.T.V.Rao MD 29

Secondary Infections:

Secondary Infections Respiratory tract infections, Otitis media Sinusitis Chronic Bronchitis Dr.T.V.Rao MD 30

Haemophilus Meningitis:

Haemophilus Meningitis Carries a High Mortality of 90% if not treated The Bacteria reach Meninges from nasopharynx Dr.T.V.Rao MD 31

Laryngo epiglottitis:

Laryngo epiglottitis Causes Epiglottis Obstructive Laryngitis > 2 years children are vulnerable Can be fatal in 2 hours Dr.T.V.Rao MD 32

Pneumonia:

Pneumonia Pneumonia along with Meningitis Lobar Pneumonia Bronchopneumonia Can present with Empyema Dr.T.V.Rao MD 33

Suppurative Lesions:

Suppurative Lesions Arthritis Endocarditis Pericarditis Haematogenous dissemination Otitis Media Cellulitis Dr.T.V.Rao MD 34

Laboratory Diagnosis:

Laboratory Diagnosis On Microscopy Gram Negative Pleomorphic organisms are seen Capsulated with polysaccharide antigen in CSF Urine also detect Antigen Dr.T.V.Rao MD 35

Culturing and Isolation:

Culturing and Isolation Can be grown on Blood agar and Chocolate agar Need 5 – 10 % carbon dioxide A streak of Staphylococcus should be streaked across the plate at 37 0 c Opaque colonies appear shows as Satellitisim Iridescence Demonstrates on Leviathan medium Blood culture Dr.T.V.Rao MD 36

Detection of Antigen:

Detection of Antigen Capsular polysaccharide antigen can be detected in CSF of Meningitis and Urine from systemic infections By Latex agglutination Counter Immuno Electrophoresis Dr.T.V.Rao MD 37

Treatment:

Treatment Cefotaxime Ceftazidime Ampicicillin, Contrimixazole Plasmid born resistance set in Ampicillin Amoxycillin with Clavulanate Clarithromycin Dr.T.V.Rao MD 38

Haemophilus influenza type b Medical Management:

Haemophilus influenza type b Medical Management Hospitalization required Treatment with an effective 3rd generation cephalosporin, or chloramphenicol plus ampicillin Ampicillin-resistant strains now common throughout the United States Dr.T.V.Rao MD 39

Epidemiology and Prevention:

Epidemiology and Prevention Similar to Pneumococci Infection enters through Respiratory tract Immunity is type specific HIB is protected by PRP vaccine Poorly immunogenic in children below 2 years Rifampicin can be given for 4 days and prevents secondary infection and eradicates carrier state. Dr.T.V.Rao MD 40

Public Health Action:

Public Health Action Dr.T.V.Rao MD 41

Current Vaccines:

Current Vaccines Haemophilus B conjugate vaccine Wide spread use of H influenza type b vaccine has reduced H influenza type b meningitis in children by 95% Dr.T.V.Rao MD 42

Newer vaccines:

Newer vaccines The previous vaccines PRP is immunogenic in older children PRP is poorly immunogenic in children below two years Immunogenicity can be improved when coupled with Protein carriers like diphtheria and tetanus Toxoid Used in young children Dr.T.V.Rao MD 43

PowerPoint Presentation:

Dr.T.V.Rao MD 44

Public Health Aspect of other Haemophilus strains:

Public Health Aspect of other Haemophilus strains H. ducreyi Sexually transmitted disease - chancroid H. influenzae biogroup aegyptius Brazilian Purpuric Fever H. aegyptius “pink eye” (purulent conjunctivitis) H. aphrophilus pneumonia Infective endocarditis Dr.T.V.Rao MD 45

H,influenzae and other Species :

H,influenzae and other Species Dr.T.V.Rao MD 46

Haemophilus ducreyi- Chancroid:

Haemophilus ducreyi- Chancroid ~5,000 cases per year in the US Major cause os STD’s Dr.T.V.Rao MD 47

Haemophilus ducreyi:

Haemophilus ducreyi Ducrey 1890 Produces Chancroid lesions Chancroid or soft sore – A Venereal disease Tender non indurated irregular ulcers of Genetalia Infection is localized spreading to only to regional lymph nodes Lymph nodes enlarged and painful Dr.T.V.Rao MD 48

H.ducreyi:

H.ducreyi Short ovoid bacilli 1 – 1.5 x 0.6 microns End to end pairing in short chains Gram –ve appear as Gram +ve Bipolar staining Bacilli in small groups appear as parallel chains giving school of fish appearance Dr.T.V.Rao MD 49

Growth and Culturing:

Growth and Culturing Grows on Fresh clotted Rabbit blood Grows on Chorioallontoic membrane of chick embryo Small grey translucent colonies are produced Dr.T.V.Rao MD 50

Chemotherapy for H ducrei:

Chemotherapy for H ducrei Sulphonamides Erythromycin Contrimixazole Ciprofloxacin Ceftriaxone Dr.T.V.Rao MD 51

Haemophilus aegypticus:

Haemophilus aegypticus Also called Koch - Weeks Bacillus Identified as Bio type of H influenza Produces pink eye Sulphonamides and Gentamycin effective Dr.T.V.Rao MD 52

H.parainflunza:

H.parainflunza Requires only V factor and not X factor Dr.T.V.Rao MD 53

H.aphrophilus:

H.aphrophilus Requires X and V factors Produces Bacterial endocarditis Brain abscess Sinusitis Abscess Dr.T.V.Rao MD 54

HACEK GROUP:

HACEK GROUP Haemophilus Para influenza H paraphorophilus Actinobacillus Cardiobacterium homnis Eikenella corrodens Kingela kingie Dr.T.V.Rao MD 55

PowerPoint Presentation:

Programme Created by Dr.T.V.Rao MD for Medical and Paramedical Students in the Developing World Email doctortvrao@gmail.com Dr.T.V.Rao MD 56