Cryptococcosis
OVERVIEW
- Cryptococcosis is a fungal infection caused by two different yeast species, that usually manifests as meningitis or pneumonia.
- cryptococcus neoformans meningitis is an AIDS defining illness
ETIOLOGY
- Cryptococcus is distributed worldwide and exists in high concentrations in bird guano, particularly pigeons and chickens (infections do NOT usually involve direct contact with birds)
- Cryptococcus neoformans (two variants – grubei and neoformans; 4 serotypes A-D) -> AIDS and immunocompromised patients
- cryptococcus gattii-> endemic to tropical and subtropical areas, travelers, increasing found in temperate areas
ASSESSMENT
Clinical manifestations (vary with species and serotype)
- meningitis – headache of insidious onset, neck stiffness often absent, fever often late
- other sites involved in AIDS: lungs, bone marrow, skin (often resembles molluscum contagiosum), and genitourinary tract
- C. gattii predominantly causes pneumonia
Investigations
- blood culture
- biopsy lesions
- CXR and/or CT chest (pneumonia)
- CT head (exclude mass lesion)
- CSF (LP must be performed even in the absence of neurological features)
— India ink stain (51% sensitive)
— MCS, high opening pressure, high protein, high WCC (low glucose if severe)
— Cryptococcal latex agglutination test for capsular polysaccharide antigen = 90% sensitive and specific (false positives if rheumatoid factor positive)
COMPLICATIONS
- immune reconstitution inflammatory syndrome (IRIS) with HAART in AIDS patients with Cryptococcal disease
MANAGEMENT
General
- Resuscitation
- supportive care and monitoring
Antimicrobial therapy
- two week induction phase, followed by an 8 week consolidation phase, and then a prolonged maintenance phase thereafter
- induction phase (2 weeks): amphotericin B (0.7 to 1 mg/kg/day) plus flucytosine (100 mg/kg/day)
- consolidation phase (8 weeks): fluconazole 400 mg daily for 8 weeks
- maintenance (at least 12 months): fluconazole (200 mg daily) is recommended once CSF sterilization has occurred
Other specific therapy
- opening pressures greater than 25 cm of CSF should be treated with serial (e.g., daily) lumbar punctures until the pressure normalizes to less than 20 cm of CSF
References and Links
CCC Neurocritical Care Series
Emergencies: Brain Herniation, Eclampsia, Elevated ICP, Status Epilepticus, Status Epilepticus in Paeds
DDx: Acute Non-Traumatic Weakness, Bulbar Dysfunction, Coma, Coma-like Syndromes, Delayed Awakening, Hearing Loss in ICU, ICU acquired Weakness, Post-Op Confusion, Pseudocoma, Pupillary Abnormalities
Neurology: Anti-NMDA Encephalitis, Basilar Artery Occlusion, Central Diabetes Insipidus, Cerebral Oedema, Cerebral Venous Sinus Thrombosis, Cervical (Carotid / Vertebral) Artery Dissections, Delirium, GBS vs CIP, GBS vs MG vs MND, Guillain-Barre Syndrome, Horner’s Syndrome, Hypoxic Brain Injury, Intracerebral Haemorrhage (ICH), Myasthenia Gravis, Non-convulsive Status Epilepticus, Post-Hypoxic Myoclonus, PRES, Stroke Thrombolysis, Transverse Myelitis, Watershed Infarcts, Wernicke’s Encephalopathy
Neurosurgery: Cerebral Salt Wasting, Decompressive Craniectomy, Decompressive Craniectomy for Malignant MCA Syndrome, Intracerebral Haemorrhage (ICH)
— SCI: Anatomy and Syndromes, Acute Traumatic Spinal Cord Injury, C-Spine Assessment, C-Spine Fractures, Spinal Cord Infarction, Syndomes,
— SAH: Acute management, Coiling vs Clipping, Complications, Grading Systems, Literature Summaries, ICU Management, Monitoring, Overview, Prognostication, Vasospasm
— TBI: Assessment, Base of skull fracture, Brain Impact Apnoea, Cerebral Perfusion Pressure (CPP), DI in TBI, Elevated ICP, Limitations of CT, Lund Concept, Management, Moderate Head Injury, Monitoring, Overview, Paediatric TBI, Polyuria incl. CSW, Prognosis, Seizures, Temperature
ID in NeuroCrit. Care: Aseptic Meningitis, Bacterial Meningitis, Botulism, Cryptococcosis, Encephalitis, HSV Encephalitis, Meningococcaemia, Spinal Epidural Abscess
Equipment/Investigations: BIS Monitoring, Codman ICP Monitor, Continuous EEG, CSF Analysis, CT Head, CT Head Interpretation, EEG, Extradural ICP Monitors, External Ventricular Drain (EVD), Evoked Potentials, Jugular Bulb Oxygen Saturation, MRI Head, MRI and the Critically Ill, Train of Four (TOF), Transcranial Doppler
Pharmacology: Desmopressin, Hypertonic Saline, Levetiracetam (Keppra), Mannitol, Midazolam, Sedation in ICU, Thiopentone
MISC: Brainstem Rules of 4, Cognitive Impairment in Critically Ill, Eye Movements in Coma, Examination of the Unconscious Patient, Glasgow Coma Scale (GCS), Hiccoughs, Myopathy vs Neuropathy, Neurology Literature Summaries, NSx Literature Summaries, Occulocephalic and occulovestibular reflexes, Prognosis after Cardiac Arrest, SIADH vs Cerebral Salt Wasting, Sleep in ICU
- Chaturvedi V, Chaturvedi S. Cryptococcus gattii: a resurgent fungal pathogen. Trends Microbiol. 2011 Nov;19(11):564-71. PMC3205261.
- Singh N, Dromer F, Perfect JR, Lortholary O. Cryptococcosis in solid organ transplant recipients: current state of the science. Clin Infect Dis. 2008 Nov 15;47(10):1321-7. PMC2696098.
- Warkentien T, Crum-Cianflone NF. An update on Cryptococcus among HIV-infected patients. Int J STD AIDS. 2010 Oct;21(10):679-84. PMC3134968.
- Wiesner DL, Boulware DR. Cryptococcus-Related Immune Reconstitution Inflammatory Syndrome(IRIS): Pathogenesis and Its Clinical Implications. Curr Fungal Infect Rep. 2011 Dec 1;5(4):252-261. PMC3289516.
Critical Care
Compendium
Chris is an Intensivist and ECMO specialist at The Alfred ICU, where he is Deputy Director (Education). He is a Clinical Adjunct Associate Professor at Monash University, the Lead for the Clinician Educator Incubator programme, and a CICM First Part Examiner.
He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives. He was one of the founders of the FOAM movement (Free Open-Access Medical education) has been recognised for his contributions to education with awards from ANZICS, ANZAHPE, and ACEM.
His one great achievement is being the father of three amazing children.
On Bluesky, he is @precordialthump.bsky.social and on the site that Elon has screwed up, he is @precordialthump.
| INTENSIVE | RAGE | Resuscitology | SMACC