1. Pathogen Disease Caused/Symptoms Diagnosis Treatment
F
U
N
G
I
Filamentous
Fungi
Microsporum Canis,
Trichophyton Rubum,
Epidermophyton
Floccosum
Infects keratinous tissues of hair, nails and
skin.
Only contagious mycosis from
humans/animals
Clinical scraping for
microscopy and culture
Clotrimazole,
terbinafine
Aspergillus Fumigatus
(ubiquitous spores)
Asthma, aspergillioma (fungal ball), invasive
aspergillosis
Systemic: lung, renal, cerebral
(immunocompromised)
Sinusitis, endocarditis
IV Amphoteracin B,
po Itraconazole or
voriconazole
Yeast-like
(mainly grow as
yeasts, but can
grow in
elongated
forms or
pseudomycelia)
Candida albicans
(opportunistic pathogen),
C. tropicalis, C. glabrata
Oral and vaginal candidiasis (thrush),
candidaemia/ endocarditis, UTI
Predisposed by: diabetes,
trauma, steroids, surgery
Wet prep. For Candida,
swabs e.g. mouth, vagina,
blood cultures in candidaemia
IV Amphotericin B
(candidaemia –
systemic)
Imidazole (mouth and
vaginal infections)
True Yeast
Cyptococcus Nefomans
(encironmental organism,
opportunistic)
Meningitis in HIV
Cancer patients, pulmonary disease
Disseminated
Clinical suspicions
Microscopy: India ink stain on
CSF
Culture: CSF, blood
Antigen detection: CSF, blood
IV Amphoteracin B,
+/- flucytosine
Difficult to eradicate
Po fluconazole
maintenance to
prevent relapse
Atypical
fungus,
previously
classified as
protozoan
Pneumocystis Jiroveci
(carinii, opportunistic)
AIDS defining illness
Seen in malignancy e.g. Hodgkins
lymphoma
Causes pneumonia – can be fatal
Microcopy/cytology of
bronchoalveolar lavage
specimens
Co-trimoxazole,
pentamidine
Dimorphic
Fungi
Histoplasma capsulatum –
yeast in tissues, mould in
environment
Asymptomatic, acute/chronic respiratory
infection, disseminated diease (liver, lungs,
spleen, esp in HIV)
IV Amphoteracin B
Blastomyces Dermatiditis RTI, skin infection IV Amphoteracin B
Coccidiodes Immitis RTI, systemic infection IV Amphoteracin B
Paracoccidiodes
brasiliensis
Skin and mucosal granuloma IV Amphoteracin B

2. P
R
O
T
O
Z
O
A
N
Sporozoa
Plasmodium Falciparum
(malignant tertian malaria)
P.vivax and P.ovale
(benign tertian malaria)
P.malariae (quartan
malaria)
Influenza-like, diarrhea and vomiting,
headache, arthralgia (joints), confusion, fits,
respiratory distress
P.vivax: chloroquine
followed by
primaquine
P.falciparum: quinine
(600mg), followed by
doxycycline
Flagellates
Giardia Lamblia
(spread person-person or
via water borne cysts)
Diarrhoea, malabsorption, partial villous
atrophy, trophozoites attach to small bowel
mucosa
Metronidazole
Leishmania donovani,
L.tropica, L.braziliensis
(sandfly = host)
(LEISHMANIASIS)
Cutaneous, mucocutaneous and visceral
clinical presentations
Amoebae
Entamoeba Histolytica
(spread person-person or
water borne cysts,
trophozoites emerge in
small bowel and invade
large bowel)
(AMOEBISASIS)
Amoebic dysentery (diarrhoea + blood),
liver abscess via spread through portal vein
Fresh stool, colon biopsy
Serum: amoebic fluorescent
antibody test
Metronidazole
(trophozoites)
Diloxanide (cysts)
Coccidia
Toxoplasma Gondii
(cat, other animals,
rodents, bird and man =
host)
(TOXOPLASMOSIS)
Asymptomatic, tissue encystation which
results in reactivation in
immunocompromised hosts;
lymphadenopathy
Lymphadenopathy - biopsy
Brain - MRI/CT scan + biopsy
Organ involvement (serology)
Only for organ
associated or sever
systemic disease
Sulfadiazine +
pyrimethamine
H
E
L
M
I
N
T
H
S
Nematodes
(roundworms)
Filariae (vectors –
mosquitoes and other
insects)
Wuchereia bancrofti
Brugia timori/malayi
Loa loa
(FILARIASES)
Adult worms reside in lymphatics or tissues
> tissue inflammation, fibrosis
Adult female releases microfilariae which
circulate the blood and tissues >
eosinophilia
Trematodes
(flukes)
S.haematobium, S.mansoni,
S.japonicum
(SCHITOSOMIASIS)
S.mansoni: blood-stained diarrohea, rectal
ulceration and fibrosis, hepatic fibrosis and
portal hypertension
S.haematobium: painless, terminal
haematuria, recurrent UTI, renal failure
4weeks: allergic reaction, fever, rash…
3months: asymptomatic egg deposition
Serology:
ELISA
Supports parasitological
diagnosis
Praziquantal (90%
curative)
Cestodes
(tapeworms)
Taenia solium (pork), Taenia
saginatum (beef),
Diphyllobothrium latum
(fish), Echinococcus (dog) –
E.granulosus
Hydatid disease (ECHINOCOCOCCOSIS)
Man: acquired by ingestion of cysts from
contact with, or food/water contaminated
with dog excreta
Liver (60%), lung (20%), rupture of liver
cyst >> multiple peritoneal cyst
Eosinophilia, +ve hyatid
CFT, US & CT scans
Albendazole and
surgery