Conference Calendar
Past Quiz Results
Revisiting ISHAM Asia 2021
The first AFWG CaseClinic is now live!
First-ever Study of Mycology Lab Practices in Asia
New Diagnostic Mycology E-learning Course
Antifungal prophylaxis: Whom, what and when
Fereydounia khargensis: A New Opportunistic Yeast Reported from Malaysia
9 Years of MMTN: Improving Fungal Disease Management in Asia Pacific
Echinocandins: Clinicians' Guide
Five controversies in mycology
Fungemia blood culture media
Deep dermatophytosis
AFWG Education Module 4: Is Antifungal Susceptibility Testing Useful for Clinical Management?
AFWG Education Module 5: TDM of Antifungal Agents - Essential or Optional?
AFWG Education Module 6: Antifungal Stewardship
10 common mistakes in laboratory mycology
Itraconazole: A Quick Guide for Clinicians
Evolving Fungal Landscape in Asia
10 common mistakes in clinical mycology
Laboratory Diagnosis of Pythiosis
ICMR Issues C. auris Advisory
Strengths and Limitations of Imaging for Diagnosis of IFI
Candidemia: Lessons Learned from Asian Studies for Intervention
Spotting invasive pulmonary aspergillosis in COVID-19 patients
Pivotal Asian Invasive Mold Study
Impact of the COVID-19 pandemic on IFI epidemiology and trends
Mycetoma in Asia: Still veiled in mystery
Identifying IFI risk factors in patients with COVID-19
ASID ANZMIG x AFWG: Fungal Frontiers in the Asia Pacific – Webinar 2
New Antifungal Agents
Gilead IFI Masterclass: Current updates on the management of IFIs in immunocompromised hosts
The AFWG Masterclass: Advanced fungal education at your fingertips
A challenging case: A crisis unfolds
The role of antifungal stewardship in improving IFI outcomes
Making Precise Diagnoses: Experience from the Laboratory Skills Enhancement Course
A challenging case: A 68-year-old man with nasal and palatal ulcers
AFWG Online Education Module 3: Optimizing Dosing in IFI Management
AFWG Online Education Module 2: Antifungal Prophylaxis in Solid Organ Transplantation
AFWG Education Module 1: The Value of Clinical Mycology Laboratories
How do I interpret Candida in the urine?
How do I interpret Candida in respiratory tract cultures?
Cryptococcosis in HIV and non-HIV infected patients
Human Pythiosis
AFWGOnline Privacy Policy has been Updated
Management of fungal infections in high-risk patients
Striving for Perfection: Experience from the Laboratory Foundation Training Course
Know your fungal landscape in Vietnam
Recent Advances of Fungal Diagnostics in Asian Laboratories
Deep Dermatophytosis: A Case Report
Management of cryptococcosis and talaromycosis
A challenging case: A 49-year-old woman with sarcoidosis
Emerging yeast infections in Asia
Outbreak of Superbug Candida auris: Asian Scenario and Interventions
Championing Medical Mycology: Thoughts on the AFWG Laboratory Skills Enhancement Course
Mucormycosis and Pythiosis – New Insights
AML and the high risk of multiple infectious complications
Do We Need Modification of Recent IDSA & ECIL Guidelines while Managing Patients in Asia?
A hospital’s experience with candidemia and empirical therapy
Top 5 most viewed AFWG videos on YouTube
Fungal Academy 2015
Fluconazole in 2015
Fungal isolation protocol
Influencing Aspergillus
Fungal Asthma
Laboratory Diagnosis of IPA
Educational Organizations
Literature Updates


10 Common Mistakes In Clinical Mycology

Share this

this page

Dr Atul Patel
Chief Consultant and Director
Infectious Diseases Clinic
Vedanta Institute of Medical Sciences
Ahmedabad, India

Mistake 1: Improper collection and processing

Clinicians overlook the value of direct microscopic examination from a clinical sample and fail to send a request to microbiology laboratory for direct microscopic examination with common stains, including wet preparation potassium hydroxide (KOH) or calcofluor white stains. Direct microscopic examination is cheap and gives you a quick result, which is useful in initiating early therapy with turnaround time of around 30 minutes.  Fungal morphology on direct microscopic exam also provide valuable information to clinicians for initiating appropriate antifungal treatment. Figure 2 shows KOH preparation from brain abscess aspirate as an example.

Figure 2. KOL preparation from brain abscess aspirate 

Mistake 2: Not requesting fungal cultures from biological samples

When clinicians do not suspect an invasive fungal infection, they can neglect to request for a fungal culture. For instance, a patient with fever of unknown origin, constitutional symptoms, and weight loss with lymphadenopathy along with adrenal enlargement (Figure 3) could be suspected of having tuberculosis (TB) in countries where TB is common like India, but this could also be a case of histoplasmosis. The patient’s clinical profile and imaging results could raise the index of suspicion. A diagnosis of histoplasmosis would be missed unless the histopathologist identifies yeast in the tissue and on hematoxylin and eosin (H&E) stain (Figure 4). Histoplasmosis is a great mimic of TB.

Figure 3. CT scan showing adrenal enlargement

Figure 4. Histopathological examination of adrenal biopsy showing multiple yeast

Mistake 3: Not being aware of drug-drug interactions

Drug-drug interactions can affect the efficacy of antifungal agents and some drug-drug interactions can be life-threatening. For instance, co-administration of rifampicin with voriconazole, fluconazole and caspofungin can significantly reduce the plasma concentrations of these antifungals, resulting in loss of antifungal activity. Concomitant use of H2 blockers or proton pump inhibitors can significantly decrease the plasma concentration of itraconazole, resulting in treatment failure. Azole antifungal agents could also significantly increase the plasma concentrations of amiodarone, which can lead to serious cardiac arrhythmias and sudden cardiac death. Similarly, azoles increase warfarin exposure and the concomitant use can lead to life-threatening bleeding.

Mistake 4: Using nephrotoxic agents concomitantly

Clinicians must be careful to avoid adding other nephrotoxic drugs in patients, particularly those in the ICU, already receiving amphotericin B. Giving aminoglycosides or other nephrotoxic agents together with amphotericin B could potentially result in severe nephrotoxicity, and renal function should be monitored frequently.

Mistake 5: Failing to adjust antifungal dosage according to renal replacement therapy

In patients with renal failure and unstable hemodynamics, the dosage of fluconazole may have to be adjusted regularly. This is a common situation in patients receiving intermittent hemodialysis. For example, an ICU patient with acute kidney injury and creatinine clearance of 10–50 mL/min requires 50% of fluconazole dosage. During the ICU course when the patient needs hemodialysis, fluconazole needs to be administered at full calculated dose after hemodialysis. Dose should be halved on the days when patient is not receiving hemodialysis. Hence, dose adjustment in such situation is a continuous process. Higher fluconazole dosage is required along with drug level monitoring in patients who are receiving continuous venvenous hemofiltration.

Mistake 6: Not monitoring QTc in ICU patients on azole antifungals

Clinicians need to be careful when managing critically ill patients receiving azoles and who also have concomitant hypomagnesemia or are also taking quinolones, clarithromycin and other drugs with potential effect on QTc prolongation. These patients could develop arrhythmias or sudden cardiac death. Electrocardiogram (ECG) monitoring should be the standard of care in ICU patients with multiple risk factors for QTc prolongation.

Mistake 7: Not practicing therapeutic drug monitoring (TDM)

TDM is a very important component of antifungal therapy in patients with invasive fungal infections and should be encouraged particularly for patients receiving voriconazole, posaconazole and itraconazole. Some clinicians believe that simply using the recommended weight-based dosage of antifungals is enough, and run the risk of treatment failure or drug toxicities. TDM ensures that patients receive the maximum benefit of antifungal treatment.

Mistake 8: Using posaconazole oral suspension as first-line treatment for mucormycosis

Mucormycosis is a life-threatening infection, and any delay in effective therapy contributes to morbidity and mortality. Amphotericin B is the usual treatment. Giving posaconazole as oral suspension should be avoided because it will take a week before steady-state level is achieved. In amphotericin B-intolerant patients, posaconazole injection or tablet formulation has better pharmacokinetics than its suspension formulation. In case where clinicians wish to use posaconazole suspension, it should overlap with amphotericin B treatment for at least 1 week before discontinuation of amphotericin B. This ensures patients have uninterrupted antifungal coverage.

Mistake 9: Treating non-albicans Candida UTI with voriconazole/echinocandins

In long-term care facilities, isolating Candida in urine is common. However, when an antifungal is indicated, using voriconazole or echinocandins is not recommended because of their poor urinary system penetration.

Mistake 10: Treating patients with Candida cultured from bronchoalveolar lavage 

Candida pneumonia is very uncommon; Candida is generally a colonizer in the respiratory system. Antifungal treatment is not required in these cases.



This field is required. Please enter your email address.
Thank you for signing up for the AFWG newsletter.
Your subscription has been updated.