Friday, 9 June 2017

Microbiology mnemonics

Some mnemonics from Microbiology

Streptococcus pyogenes: diseases caused
NIPPLES:

Necrotising fasciitis and myositis
Impetigo
Pharyngitis
Pneumonia
Lymphangitis
Erysipelas and cellulitis

Scarlet fever/ Streptococcal TS
Streptococcus pyogenes: virulence factors
SMASHED:
Streptolysins
M protein
Anti-C5a peptidase
Streptokinase
Hyaluronidase
Exotoxin
DNAses

Hepatitis: transmission routes
"Vowels are bowels":
Hepatitis A and E transmitted by fecal-oral route.

B19 virus: at-risk groups
B19 affects 3 B's:
Babies (5th disease, infectiousum erythematosa)
Black Bleeders (sickle cell anemics - anaplastic anemic crisis)
Bearing Babies [pregnant women] (hydrops fetalis

Vibrio: motility
"Vibrio Vibrates":
Vibrio is a genus of actively motile bacteria.

Endotoxin features
ENDOTOXIN:
Endothelial cells/ Edema
Negative (gram- bacteria)
DIC/ Death          
Outer membrane
TNF
O-antigen
X-tremely heat stable
IL-1
Nitric oxide/ Neutrophil chemotaxis

Teratogens: placenta-crossing organisms
ToRCHeS:
Toxoplasma
Rubella
CMV
Herpes simplex, Herpes zoster (varicella), Hepatitis B,C,E
Syphilis
· Alternatively: TORCHES: with Others (parvo, listeria), add HIV to H's, Enteroviruses.

Gram+: bacterial cell wall
· Gram+ has:
+hick pepidoglycan layer.
+eichoic acid in wall.

RNA viruses: negative stranded
"Always Bring Polymerase Or Fail Replication":
Arena
Bunya
Paramyxo
Orthomyxo
Filo
Rhabdo
· Note: Negative RNA viruses need there own polymerase.

Staphylococcus aureus: diseases caused
SOFT PAINS:
Skin infections
Osteomyelitis
Food poisoning
Toxic shock syndrome
Pneumonia
Acute endocarditis
Infective arthritis
Necrotizing fasciitis
Sepsis

RNA enveloped viruses
FORT ABC, Puerto Rico:
Flavivirus/ Filo
Orthomyxo
Retro
Toga
Arena
Bunya
Corona
Paramyxo
Rhabdo

Neisseria: fermentation of N. gonorrhoeae vs. N. meningitidis
Gonorrhoeae: Glucose fermenter only.
MeninGitidis: Maltose and Glucose fermenter.
· Maltose fermentation is a useful property to know, since it's the classic test to distinguish the Neisseria types.

Streptococci: classification by hemolytic ability
Gamma: Garbage (no hemolytic activity).
Alpha: Almost (almost lyse, but incomplete).
Beta: Best (complete lysis).

Syphilis vs. H. ducreyi (chancroid): which ulcer is painful
"In du-crey-i, you do cry (because it is painful)":
In H. ducreyi, the ulcer is painful, in syphilis the ulcer is painless.

Picornavirus: features
PICORNAvirus:
Positive sense
ICOsahedral
RNA virus

IgA protease-producing bacteria
"Nice Strip of Ham":
Neisseria
Streptococcus pneumonia
Haemophilus influenza

E. coli: diseases caused in presence of virulence factors
DUNG:
Diarrhea
UTI
Neonatal meningitis
Gram negative sepsis
· Dung, since contract E. coli from dung-contaminated water.

Meningitis: risk factors
"Can Induce Severe Attacks Of Head PAINS":
Cancer
Immunocompromised state
Sinusitis
Age extremes
Otitis
Head trauma
Parameningeal infection
Alcoholism
Infections (systemic, esp. respiratory)
Neurosurgical procedures
Splenectomy

Klebsiella
You tell the patient: "Get UPS you fat alcoholic":
UTI
Pneumonia
Sepsis
Fat capsule
Get up=nonmotile since no flagella.
Alcoholic=commonly seen in alcoholic and nosocomial patients

Urease positive organisms
PUNCH:
Proteus (leads to alkaline urine)
Ureaplasma (renal calculi)
Nocardia
Cryptoccocus (the fungus)
Helicobacter pylori

Capsulated bacteria
"Some Bacteria Have An Effective Paste Surrounding Membrane Yielding Pseudo Fort, Bypassing Killing":
Strep pneumonia
Bacteroides
H. influenza
Anthrax (B. anthracis)
E. coli
Pasteurella
Salmonella
Menigitidis (N. Menigitidis)
Yersinia pestis
Pseudomonas
Francisella
Brucella
Klebsiella

Toxoplasma gondii: clinical features
Cat reservoir: a cat.
Bug name is Gondii: cat has a Gandi head.
Cat fecal origin: cat is in the litter box.
Causes brain infection, diagnosed by CAT scan: a "CAT" scan of Gandi's brain.
Toxic to eyes: Gandi has cat eyes.
Lymph nodes enlarged: large nodes around neck.
Affects fetus: small kitten in womb.
AIDS patient commonly: cat is very skinny, like an AIDS patient.

DNA viruses: morphology rule of thumb
DNA:
Double-stranded
Nuclear replication
'Anhedral symmetry
· Rule breakers: pox (cytoplasmic), parvo (single-stranded).

Picorna viridae: members
PEECoRnA (Picorna is pronounced 'pee-corna')
Poliovirus
Echovirus
Enterovirus
Coronavirus
"R'novirus" (Rhinovirus)
Hepatitis A

Proteus: disease caused
Firstly, "PROTeus hates PROTons":
So what does it do to fight the protons? It has a urease that raises the pH.
Urea is in urine, so Proteus causes UTIs.

Diphtheria toxin properties
ABCDEF:
A/B-type toxin. Made by
Corynebacterium diphtheriae, which binds to
EF-2 (elongation factor 2).

Common cold: viral causes
"Common cold (acute infectious rhinitis, coryza) is PRIMArily caused by":
Paramyxoviruses
Rhinoviruses
Influenza viruses
Myxoviruses
Adenoviruses

Placenta-crossing organisms/ antenatal Infections
STARCH:
Syphilis
Toxoplasmosis
AIDS (HIV)
Rubella
CMV
Herpes/ Hepatitis

Toxoplasma gondii: manifestations
"My Cat Eats Mice":
Mononucleosis-like illness
Chorioretinits/ Congenital infection
Encephalitis
Myocarditis

Mycobacterium tuberculosis: culture identification

"Rough, Tough, Buff":
Rough: colony isn't smooth but rough like breadcrumbs.
Tough: colony stuck to plate well, and tough to remove.
Buff: buff is a color, a cream/coffee shade.

Staphylococci: novobiocin test to distinguish coagulase negative staphylococci
Staph epidermidis stays away from the novobiocin disc like an epidemic.
· Therefore, epidermidis is sensitive to novobiocin.
Staph saprophyticus, much friendlier, comes up to the disc and says, "'sap?'" [short for "whassup?", ie "what's up"].
· Therefore, saprophyticus is novobiocin resistant.

Tetanus: treatment for infection
SAD RAT:
Sedation
Antitoxin
Debridement
Relaxant
Antibiotic
Tracheostomy

Streptococci: Quellung reaction: positive sign, Strep type confirmed
"Quell-lung":
Quell: Capsules swell [+ve test].
Lung: S. pnuemonia [type confirmed].
· You get pneumonia in your lung.

Entameoba histolytica: disease caused, action
EntAmoeba causes Amoebic dysEntery.
Action: histo (cell) lytic (burst), so it bursts cells.

Pneumonia: causes: gram negative vs. gram positive
Gram Negatives (eg coliforms) are responsible mainly for Nosocomial pneumonia.
Gram positives (eg strep pneumonia, staph) are thus more responsible for community acquired pneumonia.

Trypanosoma brucei: disease caused
"I went on a TRYP to AFRICA":
TRYPanosoma brucei causes AFRICAn sleeping sickness.
Trichomaniasis: features
· 5 F's:
Flagella
Frothy discharge
Fishy odor (sometimes)
Fornication (STD)
Flagyl (metronidazole) Rx

Obligate anaerobes: members worth knowing
ABC:
Actinomyces
Bacteroides
Clostridium

Hemophilius: culture requirements
Read Hemophilus as "HemoFive":
· Needs Heme with Factors Five and Ten.

Pneumonia: acute pneumonia infiltrates from different causes
"Pyrogenic=PMN, Miscellaneous=Mononuclear":
Acute pneumonia caused by Pyogenic bacteria: PMN infiltrate.
Acute pneumonia caused by Miscellaneous microbes: Mononuclear infiltrate.

HIV infection: high-risk groups
HIV:
Homosexuals/ Hemophiliacs
IV drug abusers

Vaccines: types
STARK:
Subunit
Toxoid
Attenuated [live]
Recombinant
Killed [inactivated]

Chlamydia: elementary vs. initial body location
Elementary: Extracellular
Initial: Intracellular

Influenza infection: clinical manifestations
"Having Flu Symptoms Can Make Moaning Children A Nightmare":
Headache
Fever
Sore throat
Chills
Myalgias
Malaise
Cough
Anorexia
Nasal congestion

Meningitis: most common organisms
NHS:
Neisseria meningitidis
Hemophilus Influenzae
Streptococcus pneumonia
·The cause of the most Severe meningitis is Streptococcus

Endocarditis: lab results suggesting it
"High Tech Lab Results Point At Endocarditis":
Hematuria
Thrombocytopenia
Leukocytosis, -penia
Red blood cell casta
Proteinuria
Anemia
Elevated ESR

All type II reactions are related with organ specific autoimmune diseases like..
Multiple Sclerosis
Myesthenia Gravis
Chronic Thyroiditis
Graves disease
Type 1 Diabetes
Pernicious Anemia
ITP
Guillian Barre Syndrome

and all type III reactions are related to systemic autoimmune diseases like
RA
SLE
Good pastures syndrome

the concept used in Indirect flurescent Antibody (IFA)test, ELISA and Western blot...... are all the same...

that they all need a known Ag + pts serum with AB against the Ag + Antihuman gama Globulin.....with specific labels
IFA= Test ag+ pts serum+ anti- human gama globulin labeled with fluoresent dye
ELISA= test ag( P24 ag) + pts serum+ anti-Human gama globulin labeled with an enzyme.
western Blot= test ag ( GP120, GP 41, P24) + Pts serum+ anti-human gama globulin labeled with an enzyme

Functions of Interlukins

Remember the picture above: List the food items in order from left to right - HotTea, Mutton bone, EGG - All these go Into An OESophagus.
Now here are the functions:
IL-1 : Pyrogen (Hot)
IL-2 : Stimulates "T" cell (Tea)
IL-3 : Mutton BONE (BONE Marrow)
IL-4 : Stimulates IgE and IgG (EGG)
IL-5 : Stimulates synthesis of IgA and OESinophils (Into An OESophagus)

Parasitic eggs that float in saturated saline
Fertilised eggs of the following Float in saturated saline:
Remember: Imagine a DWARF holding aWHIP and PINned on ROUND HOOK
i.e. Eggs which Float are Fertilised eggs of:
Dwarf tape worm = Hymenolepis nana
Whip worm = Trichuris trichura
Pin worm =  Enterobius vermicularis
Round worm = Ascaris lumbricoides
Hook worm = Ankylostoma / Necacator

Another alternate mnemonic: I HATEFertilised eggs - HATE stands for Hook /Hymenolepis, Ascaris, Trichuris, Enterobius.

Micro organisms which don't Gram stain well
List of Microbes which may not gram stain well:
Remember: " These Microscopic Rascals May Look Colourless "
Treponema
Mycobacteria
Rickettsia
Mycoplasma
Legionella
Chlamydia

Contents of LJ Medium

Remember the picture to memorise the contents of LJ Medium ( Imagine making the special LJ Bull's eye with salt, green chilly and Pepper added )
Coagulated hen's eggs
Malachite green (Represented by green chilly)
Mineral salt
Asparaginase (Represented by PeppeR)

H. pylori
Remember the LMN: H. pylori is ......
Lophotricate
Motile
Negative gram staining

Also remember the C's
Choclate agar / Campylobacter media
Catalase +ve
CLO test +ve (= Urease breath test)
CAG is virulent cytotoxin associated gene, VAC is VACulating cytotoxin associated gene
Culture is more sensitive for diagnosis
Learn microbiology through picture mnemonics

Fever with Rash
Number of days after onset of fever that rash will appear:
Remember: Really Sick Children Must Take No Exercise.
1 Day -   Rubella
2 Days - Scarlet fever ( Also in Smallpox )
3 Days - Chickenpox
4 Days - Measles
5 Days - Typhus, rickettsia (variable)
6 Days - Nothing
7 Days - Enteric fever

Echinococcus granulosus
Echinococcus granulosus - Remember EDC
Echinococcus
Dog tapeworm is the common name
Casoni's test is used. Remember CID - Casoni's Intra Dermal test
Treatment is MAPS - Mebendazole, Albendazole, Praziquantel, Surgery