Fungi

Question 1

Sabouraud’s agar is used to grow fungi . What kind of media is it

Answer 1

Selective and is mainly used for the isolation of dermatophytes

Question 2

Name the forms of fungi and the growth characteristic of mounds and yeasts

Answer 2

Yeasts(single cells)
Connecting filaments or hyphae (mounds)

Mounds-grow by lateral branching
Elongation
Yeast-Budding

Question 3

Classification of fungi that causes diseases . Name em

Answer 3

Yeasts- have oval cells which are mainly unicellular example of true yeast - Cryptococcus neoformans

Yeast like fungi- mostly have round oval cells which bud but may form elongated filamentpus cells Called pseudohyphae which resemble the hyphae of moulds. Example- Candida albicans

Moulds or filamentous fungi- grow as branching filaments called hyphae and form mycelium . Reproduction is asexual thru spores called conidiA example Asperillus fumigatus

Dimorphic fungi- exists as yeasts at 37 degrees(parasitic phase when causing infection) and as moulds at 22 defrees(saprophytic phase in environment)
Example-Histoplasma capsulatum

Question 4

Name the types of fungal diseases

Answer 4

Hypersensitivity- body’s response to the moulds or spores. An allergic reaction is what causes a disease and not the fungi itself

Mycotoxicoses-poisoning of man by food containing fungi which then produces toxins

Mycetismus- fungi is a toxin. It’s ingested example mushroom poisoning

Infection- tissue invasion with host response

Question 5

How are fungal diseases diagnosed

Answer 5

1. Clinical suspicions (commonest way of diagnosing )
2. Microscopy using India ink,wet preparation ( take skin scrapings for this and culture if infection is superficial and if systemic take blood or sputum)
3. Culture: Sabouraud’s agar, neutral glucose peptone agar
4. Histology: Grocott’s stain
5. Antibody/Antigen example Candida precipitins
6. Skin tests: example for histoplasma

Question 6

Fungal conditions are grouped into three name them

Answer 6

Superficial mycosis- these affect hair,skin,nails and mucous membranes they include dermatophytosis and superficial candida infections

Subcutaneous and cutaneous mycosis- most develop from traumatic implantation of a fungi into the subcutaneous tissues example sporotrichosis

Systemic mycosis- spread of fungi in the blood leading to dissemination into many organs. The source may be an initial pulmonary infection. Example is invasive candida infections

Question 7

Name three genera of dermatophytes

Answer 7

Epidermatophyton : example is Epidermophyton floccosum which affects the skin
Microsporum : example is Microsporum canis and M audouini which causes epidemics of ringworm of the scalp in kids
Trichophyton rubrum : which causes recurrent skin and nails infection

Question 8

Types of Tinea

Answer 8

Tinea unguium-nails which can cause onychomycosis which can go deep into the nail bed so you don’t give medicine topical but orally else it’ll persist

Tinea corporis-skin

Tinea capitis- Scalp

Tinea cruris-groin

Tinea pedis-feet

Tinea manuum- palms

Question 9

Ringworm can survive in keratinous material for how long and is it infectious

Answer 9

8months and yes it is

Question 10

How to diagnose tinea,treatment as well and problems w treatment

Answer 10

Skin scrapings ,nail clippings and infected hair are collected for microscopy and samples can be culture on Sabouraud’s agar
Prevention and treatment: Clotrimazole, ,miconazole which are topical agents and oral agents such as terbinafine,Itraconazole

Question 11

Name some candida species and what they ar em aptly associated w

Answer 11

Albicans
Glabrata
Tropicalis

And is associated w moist skin,skin folds example under breasts between the groins,nappy rashes and people who keep their hands in water for long but don’t dry in between their fingers

Question 12

Superficial mycosis on vagina are what kind of pathogens

Answer 12

Opportunistic pathogens

Question 13

Candida albicans is a commensalism or normal flora in the vagina,mouth,on skin, and git true or false

Answer 13

True

Question 14

Oral candidiasis or thrush is not normally seen in normal people cuz it is due to very bad hygiene so which people can get it even tho they have good hygiene

Answer 14

HIV or immunocomrpomised people

Question 15

Pain in throat when swallowing in a patient with thrush means the candida has gone into the the oesophageal tract true or false

Answer 15

True

Question 16

What are the complications of candida

Answer 16

Chronic disseminated candidiasis this occurs when it goes into the eye,liver ,heart,brain

Question 17

What re the predisposing factors for overgrowth of yeast like fungi

Answer 17

Diabetes mellitus 
Malignancy 
Contraceptive pills 
HIV
Drugs example antibacterial drugs and corticosteroids (which is a dangerous medication if abused),Chronic renal failure,organ transplant

Question 18

Treatment of candida

Answer 18

Topical agents such as Nystatin gel for oral infections and clotrimazole pessaries for vaginal infections

Itraconazole and Fluconazole are used for severe infections

Question 19

Cryptococcal pulmonary infection behaves like TB . What are the symptoms of it?

Answer 19

Night sweats
Cough 
Hemoptysis 
Weight loss 
Sputum production

Question 20

Where is cryptococcus neoformans usually found,what can it result in, and what treatment is used for it

Answer 20

An encapsulated true yeast found in nature in soil contaminated with bird droppings and is transmitted by inhalation

It can result in acute pneumonia which can be complicated by dissemination of the fungus into the brains and other organs.

Treatment: use of IV Amphotericin B and in HIV patients it is followed by prophylactic use of Fluconazole which means it may be taken for years

Question 21

Cryptococcal meningitis is mainly seen among which people

Answer 21

AIDS patients

Question 22

Asperigillus behaves like asthma but is not asthma true or false

Answer 22

True

Question 23

Which Aspergillus species usually cause ear infections

Answer 23

A. Niger

Question 24

Spores of Aspergillus are ubiquitous in nature and more are found in construction sites. Inhalation leads to lung infections and in immunocompromised host can spread to sinuses and other organs which can be life threatening true or false

Answer 24

True

Question 25

Which forms of Aspergillosis are there

Answer 25

Diffuse lung infection
Fungus ball(aspergilloma)
Allergic bronchopulmonary aspergillosis which mimics bronchial asthma but is not asthma
Invasive aspergillosis

Question 26

Treatment of Aslergillosis

Answer 26

Treat w anti fungal medicine (Itraconazole,Amphotericin B)and then medicine to open the airways

Question 27

Pneumocystis jirovecii is an opportunistic pathogen among severely immunocompromised clients true or false and what does it cause

Answer 27

True
It causes atypical pneumonia primarily but dissemination can occur. It can be due to primary infection,reinfection or one of reactivation
It is stage 4 in HIV clients

Question 28

Treatment of Jirovecii

Answer 28

In HIV clients, use prophylactic co trimoxazole which is preventive for if the person hasn’t gotten it yet and treatment needs pentamidine if the person has gotten it but high dose of co trimoxazole is okay

Question 29

Jirovecii is treated w antibiotics but is classified as a fungus(yeast ) it is an atypical fungus which is difficult to study.
It’s RNA dOesnt respond to normal antibiotics for pneumonia . It is rapidly fatal .
True or false

Answer 29

True

Question 30

What is the contraindication for co trimoxazole

Answer 30

People allergic to sulphur can’t take it

Question 31

Name three drugs taken by HIV patients as a prophylaxis

Answer 31

Ceptrine which is not routinely given
Co trimoxazole
Fluconazole