Invasive fungal infections are becoming a deadly threat to high-risk populations, acting as an 'invisible infection killer' in critical care ICUs and a 'safety checkpoint for medication' after liver transplants. Voriconazole, the 'workhorse' of clinical antifungal therapy, has led to frequent missteps in empirical treatment due to soaring resistance rates and significant fluctuations in blood drug concentrations ^[1]. However, voriconazole in vitro diagnostic kits are 'precision tools' that address these clinical issues directly by using actual test data to avoid resistance pitfalls and control dosages. This safeguards the safety of medication for critically ill ICU patients and transplant recipients. Their clinical necessity is undeniable!

Many ICU patients have compromised immune systems. Combined with the use of ventilators and the overuse of broad-spectrum antibiotics, the incidence of fungal infections exceeds 35 per cent. Furthermore, the disease progresses rapidly and, for every day that effective treatment is delayed, the mortality rate increases by 10 per cent.

A critically ill patient with sepsis complicated by an Aspergillus infection was admitted to the ICU of a Grade A tertiary hospital. Despite three days of initial empirical treatment with voriconazole, the patient continued to experience a high fever and worsening respiratory failure, and their condition became life-threatening. An urgent antibiotic susceptibility test using a voriconazole in vitro diagnostic kit revealed that the causative pathogen was completely resistant to voriconazole. The doctors immediately switched the patient to a different antifungal medication to which the pathogen was susceptible. Three days later, the patient’s temperature had dropped, their symptoms had subsided, and they had ultimately recovered.

If you don't carry out accurate testing, relying solely on experience to prescribe medication will cause patients to miss the best time for treatment, which could be ineffective and even endanger their lives.

In patients who have undergone liver transplantation, liver function has not fully recovered and the ability to metabolize voriconazole is significantly reduced. The therapeutic window is more than 30% narrower than in the general population: concentrations below 1.0 μg/mL are likely to lead to treatment failure, whereas concentrations above 4.4 μg/mL result in a significant increase in hepatotoxicity. Furthermore, the coefficient of variation in individual plasma drug concentrations is as high as 94%, making dose adjustments based solely on clinical experience extremely risky. Clinical data from a transplant center shows that, among liver transplant patients not undergoing plasma drug concentration monitoring, the incidence of voriconazole-related hepatotoxicity was 28%. However, after dynamic monitoring using in vitro diagnostic reagents and real-time dose adjustments, this figure dropped to 8% ^[2].

In one case, the transaminase levels of a patient who had undergone a liver transplant doubled three days after treatment began. Testing with an in vitro diagnostic reagent revealed a blood drug concentration of 6.2 μg/ml, which far exceeded the safe upper limit. After the physician promptly reduced the dosage, the patient’s blood drug concentration returned to a safe level, their transaminase levels gradually decreased and they avoided secondary liver damage.

If you don't carry out accurate testing, relying solely on experience to prescribe medication will cause patients to miss the best time for treatment, which could be ineffective and even endanger their lives.

Backed by two core technologies, the test results match clinical treatment outcomes with over 93% accuracy, virtually eliminating false positives.

- Blood Drug Concentration Testing: Using ultra-high-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS), the clinical gold standard, this method acts like a 'precision scale' for blood drug concentrations. It can accurately determine whether levels fall within the safe range of 1.0–4.4 μg/ml, preventing underdosing or overdosing.

- Fungal Antimicrobial Susceptibility Testing: The AST-YS08 susceptibility test strips demonstrate over 90% consistency with clinical reference methods, clearly identifying whether pathogenic bacteria are 'susceptible' or 'resistant' to voriconazole. This helps physicians to avoid the pitfalls of drug resistance and eliminates the need for trial-and-error treatment ^[3].

This system is fully adaptable, whether for emergency testing of severe infections in the ICU, long-term medication monitoring for liver or hematopoietic stem cell transplant patients, or routine fungal infection screening in pulmonology and hematology departments. It can be used in laboratories in both primary care and top-tier Class A hospitals without the need for complex equipment or specialized technical teams, making it highly practical.