Aspergillosis

Aspergillosis, caused by the fungus Aspergillus fumigatus, includes four types: invasive pulmonary, extrapulmonary, allergic, and hypersensitivity pneumonitis. Aspergillosis is second to Candidiasis in causing infections in immunosuppressed patients.

CASES/YEAR
6,000 (US); 120,000 (Global)
CATEGORY
Sapronoses
AGENT TYPE
Fungi (Opportunistic Molds)
OTHER NAMES
Aspergillus fumigatus infection; Invasive aspergillosis (pulmonary); Invasive aspergillosis (extrapulmonary); Disseminated aspergillosis; Chronic aspergillosis; Aspergilloma; Allergic bronchopulmonary aspergillosis (ABPA); Allergic Aspergillus sinusitis; Extrinsic allergic alveolitis caused by Aspergillus species;
ACUITY
Subacute/Chronic
INCUBATION
Estimated 2 days to 3 months; [CCDM, p. 59]
INITIAL SYMPTOMS
Invasive pulmonary: fever, infiltrates, cough, chest pain, & hemoptysis; Extrapulmonary aspergillosis (sinuses, CNS, bone, eye, heart, gastrointestinal, & skin); Allergic (bronchopulmonary & sinuses); Extrinsic allergic alveolitis; [Cecil, p. 2052-5]
PRECAUTIONS
"Contact Precautions and Airborne Precautions if massive soft tissue infection with copious drainage and repeated irrigations required." [CDC 2007 Guideline for Isolation Precautions] "No person-to-person transmission." [CCDM, p. 60]
COMMENTS
FINDINGS
Allergic bronchopulmonary aspergillosis (ABPA) occurs in about 1-2% of patients with chronic asthma and about 7% of patients with cystic fibrosis. Patients with ABPA may eventually develop pulmonary fibrosis. Aspergillomas can cause fatal hemoptysis. The maxillary is the most common site of sinus aspergillomas. Dyspnea is a symptom of invasive pulmonary aspergillosis (IPA) and tracheobronchitis. Patients with IPA may have pleural effusions. Other reported infections are brain abscesses, meningitis, osteomyelitis, skin infection, pericarditis, and endocarditis. [PPID, p. 3108-12] Symptoms of chronic pulmonary aspergillosis are weight loss, chronic cough, and fatigue. Hematogenous spread occurs in immunocompromised patients to the brain, eye, kidney, heart, and skin. Keratitis can lead to blindness. [CCDM] In invasive aspergillosis, disseminated disease can occur in the CNS (paresis, cranial neuropathy, and seizures), GI tract (bleeding) and kidneys (flank pain and hematuria). [Cecil, p. 2052]

EPIDEMIOLOGY:
Aspergillus fumigatus has septate hyphae that branch at 45 degrees and numerous conidia (spores); it causes most cases of invasive infections and allergic syndromes and almost all cases of chronic aspergillosis. A. fumigatus spores are commonly inhaled from decomposing plant material, but immunocompetent bystanders do not usually get disease unless very heavily exposed. Profound neutropenia and glucocorticoid use are risk factors. [Harrisons, p. 594] Nosocomial aspergillosis is associated with building renovation and contaminated ventilation. [Cecil, p. 2052] Water and food may be contaminated. [CCDM, p. 59] Invasive aspergillosis imay present with nonspecific symptoms or an indolent course in immunocompromised patients. [Cohen, p. 1689]

LABORATORY:
ABPA may be associated with eosinophilia. [PPID, p. 3108] In ABPA, total IgE levels usually >1000 IU/mL; Cultures: both false positive (airway colonization) and false negative (only 10-30% of patients with invasive Aspergillus have positive cultures); [Harrisons, p. 595]

RELATED DISEASES:
See "Hypersensitivity pneumonitis," also called "extrinsic allergic alveolitis."
DIAGNOSTIC
Culture, molecular diagnosis, antigen detection, and histopathology; A suggestive sign is the halo sign on high-resolution thoracic CT (from hemorrhagic infarction around a nodule). [Harrisons, p. 595-6]
SCOPE
Global
SIGNS & SYMPTOMS
  • >fatigue, weakness
  • >fever
  • >myalgia
  • E epistaxis
  • E nasal ulcers
  • E rhinitis
  • E stomatitis
  • G blood in stool
  • G liver function test, abnormal
  • H eosinophilia
  • N headache
  • N lethargy
  • N seizure
  • O conjunctivitis, acute
  • R chest pain
  • R cough
  • R dyspnea
  • R hemoptysis
  • R sputum production
  • R wheezing
  • S papules or plaques
  • S pustule
  • S skin or subcutaneous nodule
  • S ulcer of skin
  • U hematuria
  • X cystic or cavitary lesions
  • X lung infiltrates
  • X pleural effusions
  • *ARDS
  • *arthritis
  • *blindness
  • *brain abscess or lesion
  • *cranial neuropathy
  • *endocarditis
  • *erythema nodosum
  • *meningitis
  • *myocarditis
  • *osteomyelitis
  • *pancreatitis
  • *paralysis
  • *pericarditis
  • *pneumonia
  • *pneumonitis
  • *uveitis
  • *weight loss
ANTIMICROBIC

Yes

VACCINE

No

ENTRY
Inhalation
SOURCE
Soil or Dust (Ingesting or Inhaling), Eating Contaminated Food, Eating Contaminated Produce, Waterborne (Ingesting, Inhaling, or Swimming)
RESERVOIR
RISK FACTORS
  • AIDS patients
  • Cancer patients
  • Inhale bioaerosols indoors
  • Inhale bioaerosols of moldy compost
  • Inhale moldy hay, silage, or grain
  • Inhale moldy wood dust
  • Injection drug users
  • Repeatedly inhale dust from birds
DRUG LINK
Merck Manual: Aspergillosis
REFERENCES FOR CASES/YEAR
1. (US) Second to candidiasis in number of cases of mycoses invading immunosuppressed patients; [Gorbach, p. 80] Population-based data from San Francisco suggest an incidence of 1 to 2 cases/100,000; [CDC website: Aspergillosis: Statistics] Calculate: 2/100,000 X 300 million = 6000 cases/year;
2. (Global) "Aspergillus species are ubiquitous; they are saprobic in soil and water, on various foodstuffs, and in decaying vegetation." [ID, p. 2212] Estimate global cases/yr at 20 X US cases/yr;