Symptoms of Fungal Infections in Humans
Fungal infections in humans present with a wide range of symptoms that vary depending on the type of fungus and site of infection, with most signs and symptoms being non-specific and requiring further diagnostic procedures for confirmation. 1
General Symptoms of Invasive Fungal Infections
Systemic Symptoms
- Unexplained fever despite broad-spectrum antibiotics
- Recurring febrile episodes after initial defervescence
- Drenching night sweats
- Weight loss
- Extreme fatigue (often persisting for weeks to months)
Respiratory Symptoms
- Cough
- Pleural pain or pleuritic chest pain
- Hemoptysis
- Pulmonary infiltrates during antibiotic treatment
- Dyspnea
Other Common Manifestations
- Skin infiltrations (may be misinterpreted as thrombopenic purpura)
- Sinusitis with local necrotic lesions (suggestive of mold infection)
- Headache (especially with central nervous system involvement)
Specific Fungal Infections and Their Symptoms
Coccidioidomycosis
- Respiratory symptoms similar to community-acquired pneumonia
- Fever, cough, pleuritic chest pain, headache, and rash
- Dermatologic manifestations: erythema nodosum and erythema multiforme
- Rheumatologic complaints: arthralgias of multiple joints (typically symmetrical, more in distal lower extremities, rarely with joint effusions)
- Extreme fatigue that interferes with normal activities 1
Disseminated Coccidioidomycosis
- Chronic skin ulceration or subcutaneous abscesses
- Headache (with meningeal involvement)
- Focal skeletal pain (with osteomyelitis)
- Lesions that wax and wane but are usually progressive 1
Candidiasis
- Oral manifestations: white patches on oral mucosa
- Esophageal symptoms: dysphagia and retrosternal burning
- In systemic infections: involvement of multiple organs (brain, heart, kidney, bone) through hematogenous spread 1
Aspergillosis
- Cough, pleural pain, hemoptysis
- "Halo sign" on chest CT (highly suggestive of invasive pulmonary mold infection in granulocytopenic patients)
- Central nervous system involvement in patients with hematological malignancies 1
Cryptococcosis
- Meningoencephalitis symptoms (particularly important in immunocompromised patients)
- Headache
- Detection of cryptococcal antigen in blood/CSF is highly indicative (>95%) of cryptococcal meningitis 1
Site-Specific Symptoms
Pulmonary Fungal Infections
- Cough
- Chest pain
- Hemoptysis
- Pulmonary infiltrates on imaging
- Dyspnea
Central Nervous System Fungal Infections
- Headache
- Altered mental status
- Focal neurological deficits
- Seizures
Hepatosplenic Fungal Infections
- Persistent fever
- Hepatosplenomegaly
- Increased alkaline phosphatase
- Best visualized by CT or MRI scanning 1
Gastrointestinal Fungal Infections
- Dysphagia (difficulty swallowing)
- Retrosternal burning
- Abdominal pain
- Best visualized by CT and particularly by MRI scanning 1
Skin and Soft Tissue Fungal Infections
- Local infections such as oral candidiasis
- Skin infiltrations
- Chronic skin ulceration
- Subcutaneous abscesses
Important Clinical Considerations
Diagnostic Challenges
- Symptoms of invasive fungal disease are non-specific, particularly in early stages
- Bacterial and fungal bloodstream infections cannot be clinically differentiated
- Definitive diagnosis requires histological and/or cultural evidence from tissue biopsies or positive cultures from normally sterile body fluids 1
High-Risk Populations
- Immunocompromised individuals (HIV, transplant recipients, chemotherapy patients)
- Patients with prolonged granulocytopenia
- Individuals with hematological malignancies
Diagnostic Approach
When fungal infection is suspected based on clinical symptoms:
- Obtain tissue samples for both microscopy and culture
- Consider serological testing for fungal antigens and antibodies
- Use appropriate imaging (CT, MRI) based on suspected site of infection
- In CNS, sinus, and eye infections, MRI should be preferred over CT 1
Remember that fungal infections can mimic other diseases, including tuberculosis, and should be considered in the differential diagnosis when patients present with compatible symptoms, especially if they are immunocompromised or have relevant exposure history 2.