Cryptococcosis

1
Cryptococcosis

• Bhanthumkomol P.

2
Outline

• Background
• Mycology
• Taxonomy
• Identification
• Ecology
• Epidemiology
• Pathogenicity

• Host response
• Pathogenesis
• Clinical manifestation
• Laboratory diagnosis
• Management
• Prognosis
• Prevention

3
Mycology
In vitro Specific, nutrient-poor media
Environment Human
Asexual Stage
Sexual Stage

• Two mating types form conjugation

• Budding yeast
• Haploid

Filaments
Convert to yeast form
Yeast form
Basidiospores formed by meiosis
Basidia on end
4
Taxonomy

• C. neoforman
• 2 varieties
• 5 Capsular serotypes

C. neoforman var. neoformans capsular
serotypes A D AD
C. neoforman var. gattii capsular
serotypes B C
5
Identification

• Culture
• routine laboratory agar ? 72 hr
• can grow in hemoculture
• white to cream, opaque colony on agar
• mucoid if prolonged incubation
• (Polysaccharide capsule formation)

6
Identification

• Direct test

India ink Rapid urease test Laccase activity

• Serotype identification

Commercial Antibody Glycine assimilation as
carbon source DNA analysis
Only C. neoformans
7
Ecology
var. neoformans A D AD
var. gattii B C
8
Epidemiology

• Clinical report of Cryptococcus isolation from
  human without evidence of Cryptococcosis
• COPD ? Endobronchial colonization

9
Epidemiology
Infected ?

• Access
• 1. Risk factors
• 2. Disease evidence

10
Epidemiology
Risk factors

• HIV
• Lymphoproliferative disorder CLL
• Sarcoidosis
• Corticosteroid
• Hyper IgM, IgE syndrome
• Monoclonal Ab infiximab

• SLE
• DM
• CD4 T cell lymphopenia
• Transplant
• Kidney
• Liver
• Peritoneal dialysis
• Cirrhosis

11
Epidemiology

• Serotype
• A AIDS All worldwide
• B Brazil and other Tropical
  subtropical area
• (Australia, Southeast Asia, Hawaii, Southern
  California)
• C same as B but rare
• D Denmark, Germany, Italy, France,
  Switzerland, USA

12
Transmission

• Inhalation Intensive bird exposure area
• Needlestick injury
• Organ transplant

Epidemiology
13
Capsule

• Antiphagocytosis
• Decrease complements
• Intracellular local toxicity
• Antibody unresponsiveness
• Interfere Ag presentation
• Negative charge around yeast
• Enhance HIV replication
• Dysregulate cytokine secretion
• Brain edema
• Create selectin TNF-R loss

Thicker capsule More virulence !!
Pathogenicity
14
Melanin

• Antioxidant ? tolerate oxidative stress
• Antiphagocytosis
• Decrease T cell response
• Cell wall change
• Protection from Temp. and Antifungals

Pathogenicity
15
Ability to growth at body Temp
37

• Only C. neoformans

May associated with calcineurin
Pathogenicity
16
Host response
Low Incidence Cryptococcosis
High rate Cryptococcal Infection (DH, Ab ve)
CMI
Granuloma formation
LF (CD4,CD8) inhibit growth by direct contact
Intracellular killing
Activated MF ? primary effector cell
IFN-? GM-CSF

• Phagocytes MF, PMN, Microglial cell, NK cell

Complement mediated Antibody mediated
opsonization
17

• Inhalation

Stim. Th1 response
alveoli
Contact alv. MF
3
2
1
Effective Im.Response
Dormant
Im.supp.host
Small lung or LN complex
dissemination
Crypto totally Eliminated
Clinical Cryptococcosis
Reactivation
Pathogenesis
18
Lung Normal Host
Chronic endobronchial colonization
Asymptommatic

• Prior Chronic lung disease
• No immunosuppression
• No evidence of active lung parenchymal disease
• Serum Crypto Ag Negative
• Negative CSF and urine C/S
• May have lung nodule

• 1 in 3 of cases
• Presented with Abn CXR

Acute Symptommatic

• Fever, productive cough
• Chest pain, wt loss

Clinical Manifestation
19
CXR finding

• Infiltration either lobar or interstitial
• Hilar adenopathy
• Cavity
• Pleural effusion
• Mass/ nodule

20
Serum crypto antigen

• In pulmonary crypto
• Negative ? Limited lung disease
• Positive ? Extrapulmonary source
• include LP for CSF fungus C/S
• in High risk Pt for dissemination

21
Early asymptommatic CNS

• In pulmonary crypto
• Normal CSF profile
• only positive fungus c/s

22
Lung Immunocompromised Host

• Constitutional symptom

May presented with CNS infection
ARDS
Common CXR Alv Inst. Infiltration DDX PCP
Coinfection must be worked up CMV, PCP, Atypical
mycobacteria, Nocardia
Clinical Manifestation
23
CNS

• 4 forms
• Meningitis Acute, Subacute, Chronic
• Cryptococcoma
• Spinal cord granuloma
• Chronic dementia (Hydrocephalus)

24
Cryptococcal Meningitis
25
IRIS

• Develop 1-2 mo after HAART
• Correlate with significant drop of HIV-VL
• Manifestation worsening symptom
• Acute meningitis increase Headache
• Lymphadenitis - peripheral
• - Hilar
• - Mediastinal

26
LAB

• Increase inflammatory cell in CSF
• Increase ICP ? increase headache
• But negative CSF LN aspirate C/S
• Smear may positive !! Not recommended

IRIS
27
CNS of Var gattii

• Invade brain parenchyma gt var neoformans
• Cryptococcoma hydrocephalus
• May response
• poorly to Rx
• Immuno-
• Competent
• host !!

Clinical Manifestation
28
Skin

• Marker of dissemination gt direct inoculation
• Need biopsy of Dx because of variety of skin
  manifestation
• Common papule, MP with ulcerated center
• DDX mollucum, Acne vulgaris, SCC/BCC

Clinical Manifestation
29
Prostate

• Most case ? Asymtommatic
• Sanctury site for antifungal Rx before HAART
• Dx C/S from urine or seminal fluid
• Require prolonged Rx

Clinical Manifestation
30
EYE

• Secondary to CNS occular palsies papilledema
• Small white retinal exudate w/o retinitis
• Severe immunocompromised host
• 1. occur simultaneously with HIV CMV
• 2. Extensive retinal vitritis
• - Blindness from optic neuritis
• - Blindness from increase ICP

Clinical Manifestation
31
Lab Dx

• 1. Microscopic exam.
• India ink CSF 50 positive in Non-AIDS
• 80 positive in AIDS
• Biopsy and cytology
• staining

Alcian blue
Fontana-masson
HE
Gomori
32
India ink

• Positive when CSF yeast gt 10000 CFU/ml
• Negative when CSF yeast lt 1000 CFU/ml
• Still positive during and after Treatment
• Not a marker for
  treatment failure !!

33
2. cultures

• Growth in both Bacterial Fungus media
• Isolate - biochemical DNA-based
• - Rapid urease test
• - Staibs birdseed, DOPA, Caffeic acid
  media ? melanin

Laboratory Diagnosis
34
3. serology

• Detection of Cryptococcal polysaccharide Ag
• Latex agglutination
• EIA
• False positive less likely if titer gt 14
• False negative in Early asymptomatic
  meningitis
• Chronic indolent meningitis

gt90 sensitivity and specificity
Laboratory Diagnosis
35
Remark in Serology

• Screening Crypto Ag in high incidence area in
  High risk febrile AIDS patient with headache
• CSF and Serum Crypto Ag not cross BBB
• Titer gt 11024 ? therapeutic failure

Laboratory Diagnosis
36
Remark in Serum Crypto Ag

• Serum Crypto Ag ? Screening HIV with headache
• If negative Crypto meningitis not likely !
• Not use in Follow up, Evaluate Rx response and
  relapse rate
• False ve RF ve Pt, Trichosporon
• False ve Thin capsule,
• Prozone phenomenon

Laboratory Diagnosis
37
Radiology

• CXR
• CT finding
• Normal
• Hydrocephalus
• Gyral enhancement
• Single or multiple nodule that may or may not
  enhanced
• MRI

Laboratory Diagnosis
38
MRI

• More sensitive than CT
• Numerous, clustered foci of hyperintensity in T2W
• Non-enhancing on postcontrast T1W in Basal gg
  midbrain

Laboratory Diagnosis
39
Remark in imaging

• No pathognomonic sign
• In AIDS must DDx
• Lymphoma
• Toxoplasmosis
• Nocardia
• Follow-up scan may see increased lesion from
  increased inflammatory response
• ? NOT MARKER OF Rx FAILURE

40
Management

• Cryptococal meningitis
• Amphotericin B 0.7 mg/kg/day
• Liposomal form 4 mg/kg/day toxicity decreased
• Flucytosine no monotherapy ? resistance
• Fluconazole fungistatic in suppresive phase
• Itraconazole inferior to fluco, alternative

41
Meningitis in HIV

• 3 Phases
• 1. Initial phase Ampho flucytosine 2 wk
• 2. Maintainance phase Fluco 400-800 mg/d for
  8-10 wk
• 3. Chronic suppressive phase Fluco 200 mg/d
• decrease relapse rate 50-60 ? 5

Management
42
Meningitis in Non-HIV

• 6-8 wk of Amphotericin B ? Renal toxicity
• Amphotericin B 0.5-1.0 MKD for 2wk
• then LP for CSF C/S
• if ve continue Ampho longer
• and change to Fluconazole 400 mg/d for 8-10 wk
• May consider Fluconazole 6-12mo

Management
43
Other site not meningitis

• Disseminated disease Rx as meningitis
• Lung in healthy Fluco 200-400 mg/d for 3-6
  mo
• Cryptococcoma Fluco for longer period, rarely
  need surgical intervention (lt3cm)
• Chronic endobronchial colonization ? No treatment
  !!

Management
44
Remark in Treatment relapse

• Defined by
• 1. New clinical Sign Symptom
• 2. Repeat positive C/S
• Positive india ink or Crypto Ag not precise
  indication for Relapse !!

45
Other treatment modality

• Care of increase ICP
• Repeated LP or shunt
• Detect hydrocephalus in the F/U period
• Control of HIV
• Immunomodulation
• G-CSF
• GM-CSF
• IFN-?

Management
46
Management of ICP
HIV Pt with headache
Sign and symptom of Inc ICP

• Sign of Inc ICP
• CN VI palsy
• Papilledema

• Symptom of Inc ICP
• Consciousness alteration
• Severe headache
• Visual or hearing loss

• Indication for brain imaging
• Duration gt 2wk
• Focal neurological deficit
• Papilledema, CN VI palsy

No contraindication for LP

• Coma
• VA drop / Hearing loss
• Obstructive Hydrocephalus
• LP open pr 40 cm

• LP 1-2/d
• Release CSF til Close pr lt 20 cm
• Or Close pr lt 50 Open pr
• At least 10-20 ml CSF

• Neurosurgical Consultation
• Open pr still gt 20 cm in 7 days
• Indication of Emergency CSF drainage

47
Prognosis

• Most important prognosis is ? Ability to control
  host underlying disease
• Two major prognostic finding
• Burden of yeasts at presentation
• - strongly positive india ink
• - high titer 11024
• - CSF inflammatory cell lt 20 cell/uL
• Level of sensorium at presentation
• Lucid lt Stuporous lt coma

48
Prevention

• Fluconazole prophylaxis in AIDS CD4lt100 risk
  drug resistance
• Active immunization with vaccine in high risk
  GXM-tetanus toxoid conjugate vaccine, no human
  trial
• Protective serotherapy by specific monoclonal Ab
  repeat injection
• Avoid high risk environment