1. Purulent=rapid onset, acute inflammatory exudate, bacterial causes. 

2. Aseptic=inflammation with lymphocytes, viral causes, self-limiting

3. Chronic=insidious onset, granulomatous inflammatory changes, mycobacteria or fungi causes

Chronic meningitis

bc slow growth

Cryptococcus neoformans

Coccidioides immitis

Cryptococcus neoformans

basics

Yeast (NOT dimorphic)-always

grows at 25 and 37 degrees

polysacc capsule

opportunistic=only causes meningitis in people with T cell problems

Cryptoccocus neoformans

virulence factors

1. GXM (glucuronoxylmonannan)=anti-phagocytic capsule, glistening and shiny capsule, prevents binding of complement

2. Phenyloxidase=can generate melanin-->provides a protective function to protect the organism from oxidative burst

Cryptoccocus neoformans

distribution and transmission

worldwide

soil contaminated with PIGEON droppings

inhalation

NO person-to-person

Cryptococcal Meningitis

2 forms

1. primary disease=pulmonary (asymptomatic)

-acute=rare. In AIDS patients

-chronic=nodules or masses in upper lobes, pneumonia

2. disseminated disease=

-CNS=chronic meningitis, intracerebral masses, hydrocephalus (can move easily from lungs to CSF)

-Cutaneous=papules, pustules, subcutaneous masses

Cryptococcal Meningitis

diagnosis

INDIA INK-capsule produces "halo"

CT for brain abscess (rare)

culture

agglutination test

Coccidioides immitis

basics

dimorphic fungi

TRUE PATHOGEN (infects immunocompromised AND HEALTHY peeps)

filamentous at 25/spherule at 37

warm and dry areas=soil

Coccidioides immitis

distribution and transmission

southwest U.S.

inhalation of arthroconidia (spores)-->convert to SPHERULES in the body-->rupture

DONT form yeast in the body

San Joaquin Valley Fever

can be acute self-limiting OR chronic systemic

can show hypersensitivity rxn on skin

Coccidioidomycosis

diagnosis

spherules containing endospores (in tissues)

skin test-types 4 hypersensitivity

2 from pulm lecture

1. Histoplasma capsulatum (ohio and mississippi)

2. Blastomyces dermatidis (Southeast U.S.)

2 common in IV drug users:

1. Candida albicans

2. Aspergillus furnigatus

1 common in daibetic acidosis:

Mucor species

Trypanosomiasis

basics

zoonotic disease caused by flagellated protozan

Trypanosoma

2 species

1. T. brucei gambiense and T. brucei rhodesiense (2 variations of same species). It is the African Trypanosomiasis. causes meningoencephalitis; sleeping sickness

2. T. cruzi=It is the American Trypanosomiasis. causes Chagas Disease

African trypanosomiasis

diff parts of Africa

1. West Africa (Gambien)=chronic

-Trypanosoma brucei gambiense

-reservoir=humans

2. East Africa (Rhodesian)=acute, fatal

-Trypanosoma brucei rhodesiense

-reservoir=wild game animals

T. brucei

lifecycle and virulence factors

Tryptomastigotes inoculated by tsetse bite-->go to blood and lymph-->multiply EXTRACELLULARY

-->express HVG-->evade immune system

Sleeping Sickness

3 stages

1. Chancre=localized inflammation at site of inoculation

2. Hemolymphatic stage=tryptomastigotes in blood

-recurrent fever, skin rash, lymphadenopathy, headache, IgM production (new antigenic variants every 3-8 weeks)

3. Meningocephalitic stage=tryptomastigotes in CNS

-headaches, behavioral changes, loss of consciousness

Sleeping Sickness

diagnosis

examine body fluids for presence of trygomastigotes

elevated IgM or specific antibodies

lumbar puncture

Chagas Disease

distribution

American Trypanosomiasis

Trypanosoma cruzi 

south U.S. to South Argentina

Chagas Disease

Transmission

1. contact with FECES (not bite!!!!) from TRIATOMINE BUG, REDUVIID BUG, KISSING BUG, ASSASSIN BUG

2. congenital

3. blood products/organs

T. cruzi

lifecycle and virulence

Trypomastigotes (from feces)enter at bite wound site-->invade nearby cells using PENETRIN

-->produces pore-forming protein-->transform to amastigotes-->multiply INTRACELLULARY

-->transform again to tryptomastigotes-->rupture

Chagas Disease 

clinical presentation

Acute phase=kids

-inflammation rx=CHAGOMA

-antibody and T cell rxn

-sustained febrile illness, inflammation of heart or brain

Chronic phase

-prolonged and asymptomatic

-30% develop organ damage

Chagas Disease

diagnosis

clinical findings

exposure

motile trypanosomes in body fluids

Naegleria fowleri

basics

-free-living amoeba

-found in lakes, swimming pools, tap water

-common in summer

Naegleria fowleri

transmission

Naegleria fowleri

what disease does it cause?

causes primary amebic meningoencephalitis

-severe headaches, fever, vomitting, seizures, coma, death

-weird=it causes purulent CSF!! (even though not a bacteria)

Naegleria fowleri

lifecycle

cyst form-->trophozoite-->gets DIRECTLY TO THE BRAIN

*does NOT need a human host for the cycle

Acanthamoeba

basics

Chronic granulomatous amebic encephalitis

-headaches, altered mental status

-skin lesions, keratitis, or ulcerations of cornea

-more slowly progressing than Naegleria

Acanthamoeba

diagnosis

Acanthamoeba

3 ways to get in

3 ways of getting in:

1. direct inoculation of eye

2. inhalation of organism-->infection-->blood

-->CNS

3. ulceration in skin