BACILLARY DYSENTRY SHIGELLA SPECIES Dr.Indumathi

KLEBSIELLA GRAM NEGATIVE NON MOTILE CAPSULATED LACTOSE FERMENTING(MUCOID) IMViC --++ FORMS GUT AND RESPIRATORY FLORA IN 5% NORMAL INDIVIDUALS

CLASSIFICATION 3 SPECIES” K.pneumonia ; K.rhinoscleromatis and K.ozanae PATHOGENIC LESIONS: HAEMORRHAGIC NECROTIZING CONSOLIDATION OF LUNG (1%) : UTI BACTEREMIA & OTHER FOCAL INFECTION NOSOCOMIAL INFECTION

PNEUMONIA FRIEDLANDER’S PNEUMONIA : CAP MIDDLE AGED AND OLD ALCOHOLICS SEVERE RAPID ONSET OFTEN FATAL HIGH FEVER, CHILLS, CURRENT JELLY SPUTUM ABSCESS, CAVITATION, EMPYEMA LOBAR PNEUMONIA WITH DESTRUCTIVE CHANGES : USUALLY UPPER LOBE

KLEBSIELLA PNEUMONIA

RHINOSCLEROMA K.RHINOSCLEROMATIS AFRICA, ASIA, LATIN AMERICA DESTRUCTIVE GRANULOMA OF NOSE AND PHARYNX PURULENT NASAL DISCHARGE CRUSTING LESIONS WITH NODULE RESPIRATORY OBSTRUCTION DIAGNOSIS BY HPE AND POSITIVE BLOOD CULTURE

RHINOSCLEROMA

OZENA K.OZAENAE FETID PROGRESSIVE ATROPHY OF NASAL MUCOSA NASAL CONGESTION PRIMARY ATROPHIC RHINITIS IN ELDERLY NASAL BAD SMELL HEADACHE

HISTORICAL REVIEW TERM DYSENTRY: BY HIPPOCRATES FREQUENT PASSAGE OF STOOL WITH BLOOD AND MUCOUS STRAINING AND PAINFUL DEFECATION 19TH CENTRURY : 2 FORMS OF DYSENTRY ACCURATELY SEPARATED EPIDEMICS DYSENTRY IN MILITARY CAMPS, ASYLUMS, JAILS BY SHIGELLA SPORADIC CASES OF DYSENTRY BY AMEOBA

SHIGELLA GRAM NEGATIVE SHORT RODS NON MOTILE ANAEROGENIC NON CAPSULATED GIT PATHOGEN NON LACTOSE FERMENTER COMPLEX ANTIGENIC STRUCTURE NAMED AFTER SHIGA 1896

CLASSIFICATION 4 SPECIES/SUBGROUPS BASED ON BIOCHEMICAL AND SEROLOGICAL CHARACTERS SHIGELLA DYSENTERIAE : 12 Serotypes SHIGELLA FLEXNERI : 6 serotypes SHIGELLA BOYDII : 18 SHIGELLA SONNEI : 17 Colicine types

EPIDEMIOLOGY : BACILLARY DYSENTRY PREVALENT IN TROPICS/WORLD WIDE SUMMER MONTHS POOR SANITATION OVERCROWDING /POVERTY EPIDEMICS MAN IS THE ONLY HOST : CASE/CARRIER :RESERVOIR SHORT INCUBATION (48 HRS)

EPIDEMIOLOGY CYCLIC PATTERN OF DISEASE EPIDEMICS DUE TO ONE SPECIES LASTING FOR 20-30YRS. E.G. 20TH CENTURY : S.DYSENTERIAE IN EUROPE 1926-38 S.FLEXNERI CURRENTLY S.SONNEI : IN INDUSTRIALISED COUNTRIES

EPIDEMIOLOGY INDIA ENDEMIC /HIGHLY COMMUNICABLE FOUND IN ALL AGE GROUPS ALL SPECIES : S.FLEXNERI PREDOMINANT(50-85%) S.DYSENTERIAE(8-25%) S.SONNEI (2-24%) S.BOYDII(0-8%) EPIDEMICS AND SERVERAL OUTBREAKS FROM 1974 : KERALA AND WEST BENGAL MULTIPLE DRUG RESISTANT STRAINS : CAUSING EPIDEMICS

PATHOGENESIS SOURCE : MAN: CASE OR CARRIER MODE OF SPREAD: CONTAMINATED FINGERS, FOOD, FLIES, FOMITES PERSON TO PERSON TRANSMISSION INFECTIVE DOSE: 10-100 VIABLE BACILLI HIGHEST CONCENTRATION IN STOOL DURING EARLY/ACUTE INFECTION 103 TO 109 VIABLE BACILLI PER GRAM OF STOOL POST CONVALESCENT SHEDDING : LOW COUNTS 102 TO 103

PATHOGENESIS VIRULENCE FACTORS 1.INVASIVENESS : ASSOCIATED WITH BACTERIAL PROTEIN CODED IN PLASMIDS OR CHROMOSOME. 2. TOXIN PRODUCTION : EXOTOXIN THAT IS ENTERO,NEURO AND CYTOTOXIC : SHIGA TOXIN

PATHOGENESIS INGESTED BACILLI ↓ TRANSIENTLY MULTIPLY IN SMALL INTESTINE CONCENTRATION OF 107 TO109 PER ML ENTER THE DISTAL COLON (MULTIPLY) INVADE THE MUCOSAL CELLS, MULTIPLY AND SPREAD TO ADJECENT CELLS(INTRACELLULAR SPREAD) ACUTE INFLAMMATION AND MICROABSCESS/CAP THROMOBOSIS SUPERFICIAL ULCERATION (SERPIGINOUS) ENDOTOXIN PRODUCTION TO PRODUCE BOWEL IRRITATION AND DIARRHOEA WITH BLOOD/MUCUS AND TOXEMIA

PATHOGENESIS NO BLOOD STREAM INVASION BACTERIA RAPIDLY PHAGOCYTOSED BY MACROPHAGES ENTEROTOXIN : LOCAL MUCOSAL DESTRUCTION CLINICALLY : DYSENTRY LASTS FOR 1 TO 7 DAYS SELF LIMITING HIGH MORTALITY IN MALNOURISHED COMPLICATIONS :HEMOLYTIC UREMIC SYNDROME : SHIGA TOXIN : RENAL FAILURE, TOXIC NEURITIS, ARTHRITIS RARELY : IKARI SYNDROME : MASSIVE INFECTION AND EARLY DEATH IN CHILDREN

CLINICAL FEATURES FEVER : HIGH GRADE TOXEMIA ABDOMINAL CRAMPS VOLUMINOUS WATERY DIARRHOEA FOLLOWED BY SMALL VOLUME FREQUENT PASSAGE OF BLOODY STOOLS. (OVER 10/DAY) ABDOMINAL TENDERNESS COMPLICATIONS: FEBRILE SEIZURES, SEPSIS, PNEUMONIA

LAB DIAGNOSIS SPECIMEN COLLECTION : STOOL CONTAINING MUCOUS/BLOOD RECTAL SWAB RECTAL CATHETERIZATION RECOVERY IS BEST IN THE ACUTE STAGE WHERE BACILLI ARE SHED IN LARGE NUMBERS

LAB DIAGNOSIS TRANSPORT MEDIUM BGS/CARY BLAIR ENRICHMENT : SELENITE F METHODS OF DIAGNOSIS DIRECT MICROSCOPY CULTURE SLIDE AGGLUTINATION TEST

LAB DIAGNOSIS MACROSCOPY BRIGHT RED STOOL ADHERENT TO CONTAINER ALKALINE ODOURLESS NO FAECAL MATTER SMALL QUANTITY :

LAB DIAGNOSIS MICROSCOPY NUMEROUS PUS CELLS : STAINED FEACAL SMEARS WITH METHYLENE BLUE (SINGLE MOST IMPORTANT LAB TEST OTHER THAN STOOL CULTURE) NUMEROUS DISCRETE/ROULEUX RBCS NO BACTERIA SEEN PLENTY OF MACROPHAGES GHOST CELLS : CELLS WITH NO NUCLEUS AND ONLY CYTOPLASMIC OUTLINE : PRESENT

LAB DIAGNOSIS CULTURE : MEDIA USED : FLUID : SELENITE F ENRICHMENT SOLID: MAC CONKEY’S DCA SSA STEPS : DIRECT PLATING + ENRICHMENT CULTURE GROWTH FROM FLUID MEDIUM SUBCULTURED ONTO MA

LAB DIAGNOSIS COLONIES ON MA/DCA : NLF PALE AND TRANSLUCENT COLONIES PICKED UP FOR THE FOLLOWING TESTS: HANGING DROP : NON MOTILE GRAM’S :GNB BIOCHEMICAL TESTS : IMVIC ++-- ANEROGENIC FERMENTERS SLIDE AGGLUTINATION WITH SPECIFIC HTS

BIOCHEMICAL TESTS SPECIES GLUCOSE LACTOSE MANNITOL INDOLE S.DYS ACID - V S.FLEX + S.BOYDI S.SONEI

TREATMENT AND PREVENTION ANTIBIOTICS TO BE GIVEN BECAUSE 1. PERSON TO PERSON TRANSMISSION : INFECTED PERSON IS THE RESERVOIR IN ORDER TO PREVENT THE CHAIN OF TRANSMISSION GOOD SANITATION/SAFE DISPOSAL OF SEWAGE SAFE WATER SUPPLY SHIGELLA VACCINE (ORAL: STREP DEP MUTANT:LIVE ATTEN)4 DOSES ; PROTECTION 6 MONTHS. EXP IN HYPERENDEMIC AREAS.

SALMONELLA GASTROENTERITIS * FOOD POISONING ZOONOTIC INFECTION ANIMAL OR ANIMALPRODUCTS: MEAT PRODUCTS, EGGS, CREAM, MILK (FOOD CONTAMINATION WITH RAT OR LIZARD DROPPINGS) S.TYPHIMURIUM/S.ENTERITIDIS, S.NEWPORT IP 24 HOURS DIARRHOEA, VOMITTING, PAIN ABDOMEN, FEVER