Fluconazole associated agranulocytosis and thrombocytopenia

Safety of triazole antifungals: a pharmacovigilance study from 2004 to 2021 based on FAERS

Background

Triazole antifungals are widely used as broad-spectrum antifungal activity; however, there are many undetected and unreported adverse events (AEs).

Methods

Data from the Food and Drug Administration Adverse Event Reporting System (FAERS) from the first quarter (Q1) of 2004 to the third quarter (Q3) of 2021 were selected for disproportionality analysis to assess the connection between antifungal triazoles, and AEs and important medical events (IMEs).

Results

A total of 22,566 records associated with triazole antifungals were identified, with 9584 triazole antifungal-IME pairs. The following system organ classes (SOCs) appeared as significant signals: 'Endocrine disorders' [reported odds ratio (ROR) = 167.94], 'Metabolism and nutrition disorders' (ROR = 46.30), and 'Skin and subcutaneous tissue disorders' (ROR = 21.37). Strong signals were observed with respiratory failure, rash, hepatic function abnormal, and hypokalemia. Uncommon security signals included a change in the QT interval, neurotoxicity, pseudoaldosteronism, and hallucinations.

Conclusion

Various triazole antifungals cause AEs of different types and intensities of association. Our results are broadly consistent with prescribing information and previous studies; however, additional pharmacoepidemiological studies are required to verify AEs with modest incidence but high signal.

Plain Language Summary

A study on the adverse effects of triazole antifungals Introduction: The triazole antifungals we studied include fluconazole, itraconazole, voriconazole, posaconazole, and isavuconazole. Triazole antifungals are widely used as broad-spectrum antifungals; however, there are many undetected and unreported adverse events (AEs).Materials and Methods: The Food and Drug Administration Adverse Event Reporting System (FAERS) database contains AEs reported to the FDA by different countries regarding post-marketing drugs. Through the FAERS database, we retrieved a total of 22,566 AE reports related to triazole antifungals. We not only counted information about patients' gender, age, weight, reporting country, outcome indicators, and indications but also analyzed the system organ classes (SOCs) of AEs, and the number of reported drug-related AEs and the degree of relevance.Results: We found a total of 22,566 records related to triazole antifungal agents, of which 9584 reports made important medical events (IMEs) about triazole antifungal agents, which are serious AEs. The following SOCs appear as important signals: 'endocrine disorders', 'metabolic and nutritional disorders', and 'skin and subcutaneous tissue disorders'. Triazole antifungals produce AEs, such as respiratory failure, rash, hepatic function abnormal, and hypokalemia. They also produce uncommon AEs, including changes in the QT interval, neurotoxicity, pseudoaldosteronism, and hallucinations.Conclusion: By analyzing data from the FAERS database, we identified more AEs associated with these five triazole antifungals than were indicated in the instructions and our findings provide additional insight into triazole-related AEs to inform clinicians before and during treatment.

Renal replacement therapy and concurrent fluconazole therapy increase linezolid-related thrombocytopenia among adult patients

Linezolid has been reported to be associated with thrombocytopenia. However, limited information is available on susceptibility to thrombocytopenia after linezolid usage. We aimed to investigate the risk factors for linezolid-associated thrombocytopenia (LAT). We conducted a retrospective cohort study of patients aged ≥ 18 years who received linezolid for ≥ 5 d during hospitalization in 2019. Information was extracted from electronic medical records. Thrombocytopenia was defined as a platelet count of < 100 × 10⁹/L or a reduction from baseline ≥ 25%. Binary logistic regression and survival analyses were used to evaluate the risk factors for LAT. A total of 98 patients were enrolled. Thrombocytopenia occurred in 53.1% patients, with a median of 9 d after initiation of linezolid. There was no significant difference in the mortality or proportion of platelet transfusions between patients with and without thrombocytopenia. A higher risk of LAT was found in patients who received renal replacement therapy (RRT) (OR 4.8 [1.4–16.4]), or concurrent fluconazole (OR 3.5 [1.2–9.8]). Patients who received RRT (8 vs. 15 d) or concurrent fluconazole (11 vs. 15 d) had a shorter median time to develop thrombocytopenia. Those who simultaneously received RRT and fluconazole had the shortest median of time (6.5 d) and the highest risk of developing thrombocytopenia (87.5%).

Staphylococcus lugdunensis Urinary Tract Infection With Associated Neutropenic Fever

We present a 62-year-old woman with a history of uterine cancer status post-total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH-BSO) on paclitaxel, who presented to the emergency department febrile at 101.7 Fahrenheit and complaining of fatigue and urinary incontinence. Laboratory testing revealed neutropenia and urinalysis showed elevated bacteria with minimal white blood cells, and negative leukocyte and negative nitrites. Urine cultures ultimately showed Staphylococcus lugdunensis with negative blood cultures.

S. lugdunensis is a less frequently speciated Staphylococcus and has been increasingly found due to advances in identification using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). S. lugdunensis are Gram-positive cocci, nonsporulating, nonmotile, facultatively anaerobic, catalase-positive, coagulase-negative, oxidase-negative, delta-hemolytic organism. Traditionally, it is seen in skin and soft-tissue infections, as well as vascular infections, however, has minimal occurrences in urinary tract infections.

The risk of infection is increased in immunocompromised states and empiric treatment is warranted while waiting for definitive results. Our patient was started on cefepime, valacyclovir, fluconazole, and a single dose of vancomycin while in the emergency department. Worsening thrombocytopenia during her antibiotic course necessitated the re-evaluation of antibiotic agents which can cause thrombocytopenia. Subsequently, due to the patient’s improved clinical status, and low risk of severe outcome, fluconazole and valacyclovir were discontinued, and cefepime was changed to ceftriaxone.

Acute fluconazole toxicity: a case presenting with protean manifestations including systemic and neurologic symptoms

Neurologic adverse effects of triazole antifungal compounds used for the treatment of systemic and deep mycoses are relatively rare. The most common presentation is the involvement of peripheral nervous system, usually presenting with subjective symptoms such as paresthesia, dysesthesia, or numbness. Among these compounds, fluconazole has relatively more frequent neurological adverse reactions.A 54-year-old man was admitted with numbness and weakness in his both feet, which gradually worsened and resulted in difficulty in ambulation over time. He had no morbidity other than hypertension. He developed polyneuropathy (PNP), lower gastrointestinal system bleeding, acute renal insufficiency, thrombotic thrombocytopenic purpura, and confusional state. Severely disabling axonal and demyelinating sensorimotor PNP which led to immobilization of the patient for a few weeks but was recovered. When a more detailed past medical history was taken, he admitted to ingestion of 200 mg/day fluconazole for 1 month for onychomycosis without any prescription. This unusual combination of these rare adverse reactions of fluconazole may be explained by activation of an immune mechanism triggered by the drugs and genetic factors, or some other unknown individual factors.This case is reported due to the presence of rare systemic and neurologic adverse events of fluconazole, leading to this unusual clinical picture. We would like to emphasize fluconazole-related systemic and neurologic adverse reactions with life-threatening potential should be kept in mind.

Rapid-Onset Thrombocytopenia Following Piperacillin-Tazobactam Reexposure

Drug-induced thrombocytopenia is a rare but serious adverse event that has been associated with multiple drugs including β-lactams. Although it mostly occurs with prolonged medication use, some cases of rapid-onset thrombocytopenia have been reported. We describe the case of a 69-year-old man who developed severe and immediate thrombocytopenia following reexposure to piperacillin-tazobactam in the critical care setting. He received a 6-day course of piperacillin-tazobactam for a possible pneumonia immediately after cardiac surgery. During this course of therapy, his platelet count decreased (fluctuating between 69 × 10(3) /mm(3) and 104 × 10(3) /mm(3) ) and then progressively increased after completion of the antibiotic to 340 × 10(3) /mm(3) on postoperative day 15. Ten days after the antibiotic course was completed (postoperative day 16), the patient developed new signs of infection (fever and neutrophilia), and piperacillin-tazobactam was restarted. Eight hours after reintroducing the antibiotic, his platelet count dropped from 317 × 10(3) /mm(3) to 7 × 10(3) /mm(3) . After reviewing all the medications administered to the patient as well as other potential causes of thrombocytopenia, and given the chronology of events, piperacillin-tazobactam was suspected as the most likely offending agent and was therefore replaced by meropenem on postoperative day 17. The patient's platelet count began to rise 2 days after discontinuation of piperacillin-tazobactam and reached 245 × 10(3) /mm(3) by postoperative day 30. No spontaneous bleeding or thrombosis occurred while the patient was thrombocytopenic. Use of the Naranjo Adverse Drug Reaction Probability Scale indicated a probable relationship (score of 6) between the patient's development of thrombocytopenia and piperacillin-tazobactam therapy. This case highlights the severity and swiftness in which drug-induced thrombocytopenia may present in the context of cardiac surgery.