The Impact of a Laboratory Error on a Patient’s Well Being: A Case Report on Overdiagnosis and Its Consequent Iatrogenesis

Overdiagnosis, resulting from excessive use of diagnostic tests, can lead to unnecessary treatments and negatively impact patients' quality of life. This case highlights the importance of prescribing tests based on the best scientific evidence to avoid emotional and financial harm to patients while promoting quaternary prevention. A 77-year-old woman, undergoing surveillance for a thyroid nodule, mistakenly underwent a urinary cytology test, which revealed a suspicious finding. Due to this incidental result, the Family Physician referred her to a Urology consultation to rule out urothelial cancer. The subsequent investigations included renal and pelvic CT scans, urethrocystoscopy, and repeated urinary cytology, all of which yielded negative results for malignancy. Throughout this process, the patient experienced anxiety, sadness, and loss of appetite, which also affected her family life. The test requested by the Family Physician was a non-cervicovaginal exfoliative cytology, which can encompass various types of cytology. However, due to a laboratory error, urinary cytology was performed instead of a fine-needle aspiration cytology (FNAC) of the thyroid. This mistake led to an unfounded suspicion of cancer, causing significant anxiety for the patient and her family. The cascade of invasive tests and the use of limited healthcare resources underscore the dangers of overdiagnosis and the challenge of maintaining healthcare system sustainability. This case illustrates the importance of quaternary prevention, encouraging a cautious approach to ordering diagnostic and therapeutic tests, as well as involving patients in informed decision-making regarding their health. The role of the Family Physician is crucial in understanding patients' concerns and needs, promoting a holistic, patient-centered approach to healthcare delivery.