Histology Slides Database: February 2013

Wednesday, February 27, 2013

Polymorphonuclear neutrophils and Immunity

Polymorphonuclear neutrophils and Immunity

Polymorphonuclear neutrophils,

–also called polys for short,

–are phagocytes that have no mitochondria and get their energy from stored glycogen.

–They are nondividing, short-lived (half-life of 6–8 hours, 1–4 day lifespan), and have a segmented nucleus.

–[The picture below shows the neutrophil phagocytizing bacteria, in yellow.]

–They constitute 50–75% of all leukocytes.

–The neutrophils provide the major defense against pyogenic (pus-forming) bacteria and are the first on the scene to fight infection.

–They are followed by the wandering macrophages about three to four hours later

Tuesday, February 26, 2013

Treatment for Campylobacter infection

Treatment for Campylobacter infection

•Fluid and electrolyte replacement is central to the treatment of diarrheal illnesses

•The in vitro susceptibility of Campylobacter species to macrolides such as clarithromycin and azithromycin suggests that these antibiotics would also be useful therapeutic agents.

Viva questions for Pathology & Histopathology

Viva Question for Pathology & Histopathology are listed below :

Define Carrier
Difference between carrier of HBB and HBC
What is dysgerminoma
Definition of urolithiasis. Give colour, surface, pH and sensititivity of different crystals
What is Meig’s syndrome? Ascities, fibroma and hydrothorax.
Define dysuria
Define occult carcinoma
Prognosis of renal cell carcinoma
Mention the commonest cause of painless haematuria
Mechanism of Hyperlipidemia in nephrotic syndrome
What is desmoplasia
Mention commonest places for metastasis
Define Neoplasia
What is breast mouse (fibroadenoma)
Differentiate between serum and plasma
Differentiate between acute and chronic inflammation
Differentiate between exudate and transudate
Type of ascites in cirrhosis (transudate)
Type of fluid in inflammation (exudate)
What is anuria (no urine in 24 hours)
Causes of renal failure (primary and secondary)
Define metastasis
What is milk alkali syndrome(hypercalcemic syndrome)
Type IV hypersensitivity (TB (montoux test), coccidioidomycosis (spherulin test))
Differentiate between nephritic and nephrotic syndrome
Define uremia
Define azotemia(increased level of creatinine and urea)
Define papilloma
Define polyp
Sites of squamous cell carcinoma
Sites of metaplastic squamous cell carcinoma
What is difference between fibroadenoma and carcinoma of breast
Differentiate between adenomyosis and endometriosis
Define granuloma
Give criteria for granuloma (epitheloid cells)
Morphology of hepatitis C
Morphology of HBB
What is the difference chronic active and chronic persistent Hep.(enzymes)
What is Stein leventhal syndrome
What is hepatoblastoma
Define dysplasia
Which carcinoma which doesn’t metastasize (basal cell carcinoma)
Osteoclastoma type of cells (giant cells and mononuclear stromal cells)
Which are malignant cells in the cell population of osteoclastoma (mononuclear cells)
Differentiate between hypertrophy and hyperplasia
Differentiate between atrophy and aplasia
Functions of liver
Functions of kidney
What is sterile pyuria(no detectable microbes but pus cells are present eg. TB and prior antibiotic therapy, gram negative organisms)
Difference between Hodgkins and NHL
Types of granuloms (caseating, non-caseating, foreign body, necrotizing)
Where does caseating granuloma appear (most common TB and fungal)
Where does non-caseating granuloma appear (sarcoidosis, Crohn’s disease)
Define menorrhagia
What is dysfunctional uterine bleeding
Differentiate between epitheloid and epithelial cells
Types of leiomyoma
Sites of leiomyoma (GIT, uterus)
Classify tumours
Give differences between benign and malignant tumours
Normal urea level in urine
How will you collect urine samples in 24 hours.
Lab diagnosis of acute lymphoblastic leukemia
Define inflammation

Treatment for shigellosis/bacterial dysentry

Treatment for shigellosis/bacterial dysentry

•The organisms are usually susceptible to Ciprofloxacin,ampicillin,Septran, tetracycline,and chloramphenicol

•MDR are widespread.MDR is plasmid borne and can be transmitted.

•An antitoxin is available against shigella dysenteriae type I exotoxin

•No vaccination -no prophylactic antimicrobials

•No anti peristalsis they prolong the excretion and symptoms

Acquired immunity for Shigellosis/shigella infection

Acquired immunity for Shigellosis/shigella infection

• acquired immunity is serotype-specific, an individual can be infected multiple times by different serotypes.

•Antibodies are formed but not protective because the microorganism does not invade the blood stream

Serology for Shigella/bacterial dystentry

Serology for Shigella/bacterial dystentry

•The antisera are available commercially

•The organisms are subcultured on to non selective medium.

•The organism harvested,suspended in fluid medium,standardised as per manufacturer Instructions

•They are allowed to react with group antisera IN SLIDE AGGLUTINATION TESTS.

Infectious dose OF Shigella

Infectious dose OF Shigella

•Shigella is highly host-adapted and is a natural pathogen only of humans and higher primates.

•One of the most effective among the enteric bacteria

•cause infection and illness in humans with a very small number of ingested bacteria, from a few hundred to a few thousand organisms.

Antigenic structure of genus Shigella

Antigenic structure of genus Shigella

•There are somatic antigens

•Some shigella do have surface antigens called K antigens

•There are 43 serotypes of shigella on the basis of O antigens .

Growth Characteristics of Shigella

Growth Characteristics of Shigella

•Like all the members of family enterobactreiacae

–they grow anaerobically as well as aerobically.

•Shigella grows better in aerobic environment

Habitat Of Shigella

Habitat Of Shigella

•They live in the intestine of human beings and primates.

•They cause bacillary dysentery.

• Bacteria are transmitted from person to person through faeco-oral route.

ETIOLOGIC AGENT Of Shigellosis

Etiologic Agent OF Shigellosis

•Members of the family Enterobacteriaceae

– tribe Escherichieae.

•These are closely related to Escherichia coli

•The two genera cannot be distinguished by DNA hybridization methods.

•Shigellae are now thought to be differentiated pathogenic E. coli

•Shigellae are small, gram-negative, non motile bacilli

•cocobacillary forms occur in young cultures

•Four Species of shigellae

–Shigella dysenteriae

–Shigella flexneri

–Shigella boydii

–Shigella sonnei

DEFINITION Of Shigellosis

DEFINITION Of Shigellosis

•Shigellosis is an acute infectious inflammatory colitis due to one of the

members of the genus Shigella.

•The disease is often referred to as “bacillary dysentery”.

Monday, February 11, 2013

Morphology Of Vibriocholerae

Morphology Of Vibriocholerae

•Vibrio cholera is curved rod ,comma shaped

• 1-2 um in size .

•it is actively motile and has typical darting motility

•On prolonged incubation the vibrios tend to become straight rods.

• all vibrios are halophilic (i.e., require salt for growth) except V. cholerae and V. mimicus

Cultural characters Of Vibriocholerae

Cultural characters Of Vibriocholerae

•The ph range at which vibrios grow is 8.5-9.5 .

•They are killed by acid

•On non selective media vibrio produces

– convex smooth colonies that are opaque and granular

•The vibrio cholera can grow over a wide range of temperature

– the optimum temperature is 37oC.

•Can grow on a wide variety of culture media

–Simple

–Enriched

–Selective

– chemically defined media containing asparagine and mineral salts as sources of nitrogen and carbon.

•Vibrio cholerae produces oxidase.The oxidase test differentiates it from enterobacteriacae

•Susceptibility to compound 0/129 differentiates it from aremonas.vibrio is sensitive to O/129 .Aremonas is resistant

•Thiosulphate citrate bile sucrose medium(TCBS)-vibrios can grow on this selective medium.produce yellow sucrose fermenting colonies –oxidase positive

Habitat Of Vibriocholerae

Habitat Of Vibriocholerae

• vibrios most commonly reside in rivers under conditions of moderate salinity

• coastal salt water

•Shell fish and other seafood

•They proliferate more rapidly in the summer months when water temperatures exceed 20°C.

•the illnesses they cause also increase in frequency during the warm months.

Classification Of Vibriocholerae

Classification Of Vibriocholerae

On the basis of the carbohydrate determinants of their lipopolysaccharide (LPS) O antigens some 200 types have been identified

They are divided into two groups

•01 group

•NON 01 group

•biotypes of V. cholerae O1,

Based on differences in biochemical tests

– classical

– El Tor,

Each biotype is further subdivided into three serotypes,

• Inaba

• Ogawa.

•Hikojima

What are Rice Water Stools ?

What are Rice Water Stools ?

• The stool has a characteristic appearance:

• a nonbilious, gray, slightly cloudy fluid with flecks of mucus,

• no blood, inoffensive odor.

•It has been called "rice-water" stool because of its resemblance to the water in which rice has been washed. These are seen in infection by vibriocholerae.

How stool sample suspected to have Vibriocholerae be transported?

How stool sample suspected to have Vibriocholerae be transported?

•For short delays with a more certain diagnosis of cholera cary Blair is still good.

•For longer delays alkaline peptone water is used as a transport medium.

•Cary Blair medium should be used if salmonella and shigella are also suspected.

Is vaccine available for Vibricholerae ?

Is vaccine available for Vibricholerae ?

•Killed vaccine is available

•Gives short lived protection for about 6 months

•Research for improved vaccines including live attenuated oral vaccine

General characters of the family Enterobacteriaceae

General characters of the family Enterobacteriaceae

•Gram negative rods

•Motile or non motile

•If motile with peritrichious flagella

•Aerobic or facultative anaerobe

•Catalase positive

•Oxidase negative

•Ferment glucose with or without production of gas

• Reduce nitrates to nitrites

•Morphology gram negative non sporing

•Motility

•Culture

–Simple media they can grow very easily

•Why the selective media are used then

•To Knock out the normal flora

Routes of transmission Of Salmonella

Routes of transmission Of Salmonella

•Oro faecal through food and water

•Rarely through contaminated hands

• Health care workers occasionally acquire enteric fever after exposure to infected patients

•while laboratory workers can acquire the disease after laboratory accidents.

Biochemical tests which help to differentiate the members of family enterobacteriaceae

Biochemical tests which help to differentiate the members of family enterobacteriaceae

•Motility

•IMVIC

•Fermentation of sugars

•Urease test

•Decorboxylation of amino acids

•Deamination of amino acids

•ONPG test

•Gelatin liquification test

•Grtowth in the presence of KCN

•Edward’s and Ewing

•Bergy’s Manual

•

Predisposing factors to Infection by Salmonella in humen

Predisposing factors to Infection by Salmonella in humen

• Conditions that decrease stomach acidity

–an age of <1 year,

–antacid ingestion, or

– achlorhydric disease

•conditions that decrease intestinal integrity increase susceptibility to Salmonella infection.

– inflammatory bowel disease,

– history of gastrointestinal surgery,

• alteration of the intestinal flora by antibiotic administration

•High incidence in schistosomiasis areas the organisms adhere to adult worms

•

How Salmonella overcomes body’s defences to cause disease ?

How Salmonella overcomes body’s defences to cause disease ?

•the Vi antigen

– It forms a capsule to protect the bacterium from complement and from phagocytic(PMN) immune cells.

– the Vi antigen, further protect themselves from lysis within the macrophage

•The very presence inside the macrophages helps to escape the adverse conditions outside the macrophages

•they are protected from polymorphonuclear leukocytes (PMNs), the complement system, and the acquired immune response (antibodies)

•There are mechanisms which help the bacteria to overcome the hostile environment in side the macrophages

– The bacterium produces homocysteine to inactivate nitric oxide and enzymes

•The infected macrophage provides Salmonella a vehicle safe from other elements of the immune system and in which it can multiply and travel.

•The microorganism causes the apoptosis in the macrophages and enters the bloodstream to attack the rest of the body.

•M cells are epithelial cells that mature into professional phagocytes reside within Peyer's patches. Immobile and interspersed among regular enterocytes in Peyer patches,

•bacteria-mediated endocytosis (BME).helps to overcome the innate defenses in the small intestine