Making Precise Diagnoses: Experience from the Laboratory Skills Enhancement Course

By Dr Chi-Jung Wu

What did you find interesting about the detection and diagnostic methods used?

It was an honor to have Dr Ariya Chindamporn (associate professor at the Department of Microbiology of the Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand), one of the leading experts in medical mycology in Asia, as my tutor. I began my course at the clinical microbiology laboratory (mycology unit) of King Chulalongkorn Memorial Hospital (KCMH), where Dr Ariya supervised the fungal diagnostics work.

At KCMH, physicians emphasized on direct microscopic examination of clinical fungal specimens with KOH preparation or fungal stains. This practice allowed earlier detection and characterization of causative fungi, hence making prompt and appropriate antifungal therapy possible.

Dr Ariya’s laboratory is one of the few in Asia that performs the β-D-glucan assay, a diagnostic tool for fungal infections. I was very impressed by the delicate work involved in performing the β-D-glucan assay, with all the laboratory conditions strictly controlled in order to achieve accurate data.

The cryptococcal antigen lateral flow assay (CrAg LFA) was also new to me, since most clinical microbiology laboratories in my country adopted the latex agglutination test for CrAg detection. CrAg LFA is a low-cost, user-friendly, point-of-care test for rapid, sensitive and specific detection of CrAg – it detects all serotypes, while the latex agglutination method has reduced sensitivity for CrAg serotype C. Therefore, CrAg LFA is highly recommended for initial screening tests and for use in settings with no or minimal infrastructure and manpower.

Although utilizing polymerase chain reaction (PCR) for fungal identification and detection through internal transcribed spacer (ITS) or D1/D2 sequencing has been well developed, it is rarely applied in clinical routine laboratories. At KCMH, physicians can order PCR tests for isolate identification and fungal detection directly for clinical samples. This was truly helpful and facilitated targeted treatment. The close collaboration between the research laboratory and clinical routine laboratory greatly enhanced the diagnostic capacity at KCMH.

What other experience did you gain from the course?

It was a pleasure to view a large collection of yeast and mold teaching slides, and to receive one-on-one lectures from Dr Ariya and Dr Arsa. For the first time, I viewed many beautiful fungal sporulation and clinical specimens visualized by KOH preparation or fungal stains. The slide viewings and lectures gave me a better understanding of fungal taxonomy and ways to identify fungi by morphologic characteristics.

Thailand has the highest incidence of human pythiosis in the world and many cases were treated at KCMH. I was given a hands-on experience to perform a serology test to detect serum-specific total IgG against Pythium insidiosum using enzyme-linked immunosorbent assay (ELISA) which was established by Dr Ariya’s laboratory. I also learned new molecular diagnostic tools for pythiosis, recently developed by Dr Ariya and Ms Worasilchai Navaporn. From their experience sharing, I learned how to design user-friendly diagnostic tools that are potentially applicable to other infectious diseases.

The training course also incorporated a teaching ward round of patients with infectious diseases at KCMH. Dr Rongpong Plongla took me through how infectious disease physicians at KCMH diagnosed and treated patients. The clinical application of 16S and ITS (D1/D2) sequencing directly on clinical samples for suspected bacterial and fungal infections, respectively, made targeted therapy or de-escalation of antimicrobial therapy possible. We also discussed about interpreting the results and limitations of such methods.

Additionally, I had the opportunity to visit the National Center for Genetic Engineering and Biotechnology and the Thailand Bioresource Research Center (TBRC), one of the largest biobanks among the Association of Southeast Asian Nations (ASEAN) countries. Dr Lily Eurwilaichitr, Ms Suwanee and their colleagues introduced ways to achieve sustainable utilization of bioresources and ways to broaden international life scientists’ access to biomaterials using information technology. Their introduction provided me with more insight into how a biobank operates in the real world.

How would you apply what you have learned back to your home country?

In my home country, I am involved in a mycology reference laboratory and local training and educational activities. The course has enhanced my knowledge about fungal diagnostics and biobanks, which will definitely contribute to my work.

Dr Ariya generously shared with me a large collection of teaching slides of both yeast and molds. I would also like to make my own sets of mycology teaching slides, which would be a great aid for anyone planning to view many medically important fungi in a short period.

Additionally, I will continue improving PCR techniques for fungal diagnostics with the hope to apply this in clinical settings, as implemented at KCMH and Dr Ariya’s laboratory. I also hope to enhance clinical and laboratory alertness for human pythiosis among physicians and medical technicians.

Any final thoughts on the course?

I would like to express my immense gratitude to AFWG which opened the door for me to join the program, and to Dr Ariya and her team members at Chulalongkorn University who were all generous in sharing their experience and passionate about advancing the knowledge of medical mycology. It is highly important that AFWG can continue offering such courses to laboratory practitioners who are interested in fungal diagnostics and committed to achieving their goals. This will strengthen connections between researchers and fungal laboratories in different Asian countries, helping each country advance towards state-of-the-art diagnostics of fungal infections.

Dr Wu attended the AFWG Laboratory Skills Enhancement Course from December 25, 2017 to January 26, 2018 at the Chulalongkorn University, Bangkok, Thailand.