WebM&M: Case Studies
WebM&M (Morbidity & Mortality Rounds on the Web) features expert analysis of medical errors reported anonymously by our readers. Spotlight Cases include interactive learning modules available for CME. Commentaries are written by patient safety experts and published monthly.
Have you encountered medical errors or patient safety issues? Submit your case below to help the medical community and to prevent similar errors in the future.
This Month's WebM&Ms
A 38-year-old man with end-stage renal disease (ESRD) on chronic hemodialysis was admitted for nonhealing, infected lower leg wounds and underwent a below-knee amputation. He suffered from postoperative pain at the operative stump and was treated for... Read More
A 5-day old male infant was admitted to the pediatric intensive care unit (PICU) and underwent surgery to correct a congenital heart defect. The patient’s postoperative course was complicated Staphylococcus aureus bacteremia and other problems,... Read More
This WebM&M highlights two cases of hospital-acquired diabetic ketoacidosis (DKA) in patients with type 1 diabetes. The commentary discusses the role of the inpatient glycemic team to assist with diabetes management, the importance of medication... Read More
These cases describe the rare but dangerous complication of hematoma following neck surgery. The first case involves a patient with a history of spinal stenosis who was admitted for elective cervical discectomy and cervical disc arthroplasty who went... Read More
A 27-year-old pregnant woman was diagnosed with severe pulmonary arterial hypertension at 29 weeks estimated gestational age (EGA) and admitted for elective cesarean delivery with lumbar epidural anesthesia at 36 weeks EGA. After epidural catheter... Read More
All WebM&M: Case Studies (32)
This case describes a man in his 70s with a history of multiple myeloma and multiple healthcare encounters for diarrhea in the previous five years, which had always been attributed to viral or unknown causes, without any microbiologic or serologic testing. The patient was admitted to the hospital with gastrointestinal symptoms and diagnosed with cholecystitis and gangrenous gallbladder. Two months after his admission for cholecystitis, he was readmitted for severe vomiting and hypotension. An upper gastrointestinal endoscopy with biopsy unexpectedly showed that his duodenum was heavily infiltrated with a parasitic helminth (worm) called Strongyloides stercoralis. He was treated with the anti-parasitic drug ivermectin and eventually improved enough to be discharged from the hospital. The commentary summarizes factors contributing to the missed diagnosis of strongyloidiasis, potential consequences of a failure to diagnose this infection, and approaches to identify patients who should be tested for Strongyloides infection.
A 49-year-old woman was referred by per primary care physician (PCP) to a gastroenterologist for recurrent bouts of abdominal pain, occasional vomiting, and diarrhea. Colonoscopy, esophagogastroduodenoscopy, and x-rays were interpreted as normal, and the patient was reassured that her symptoms should abate. The patient was seen by her PCP and visited the Emergency Department (ED) several times over the next six months. At each ED visit, the patient’s labs were normal and no imaging was performed. A second gastroenterologist suggested a diagnosis of intestinal ischemia to the patient, her primary gastroenterologist, her PCP, and endocrinologist but the other physicians did not follow up on the possibility of mesenteric ischemia. On another ED visit, the second gastroenterologist consulted a surgeon, and a mesenteric angiogram was performed, confirming a diagnosis of mesenteric ischemia with gangrenous intestines. The patient underwent near-total intestinal resection, developed post-operative infections requiring additional operations, experienced cachexia despite parenteral nutrition, and died of sepsis 3 months later. The commentary discusses the importance of early diagnosis of mesenteric ischemia and how to prevent diagnostic errors that can impede early identification and treatment.
A 65-year-old woman with a history of 50 pack-years of cigarette smoking presented to her primary care physician (PCP), concerned about lower left back pain; she was advised to apply ice and take ibuprofen. She returned to her PCP a few months later reporting persistent pain. A lumbar spine radiograph showed mild degenerative disc disease and the patient was prescribed hydrocodone/acetaminophen in addition to ibuprofen. In the following months, she was seen by video twice for progressive, more severe pain that limited her ability to walk. A year after the initial evaluation, the patient presented to the Emergency Department (ED) with severe pain. X-rays showed a 5 cm lesion in her lung, a small vertebral lesion and multiple lesions in her pelvic bones. A biopsy led to a diagnosis of lung cancer and magnetic resonance imaging (MRI) showed metastases to the liver and bone, as well as multiple small fractures of the pelvic girdle. Given the extent of metastatic disease, the patient decided against aggressive treatment with curative intent and enrolled in hospice; she died of metastatic lung cancer 6 weeks after her enrollment in hospice. The commentary summarizes the ‘red flag’ symptoms associated with low back pain that should prompt expedited evaluation, the importance of lung cancer screening for patients with a history of heavy smoking, and how pain-related stigma can contribute to contentious interactions between providers and patients that can limit effective treatment.
A 44-year-old man presented to his primary care physician (PCP) with complaints of new onset headache, photophobia, and upper respiratory tract infections. He had a recent history of interferon treatment for Hepatitis C infection and a remote history of cervical spine surgery requiring permanent spinal hardware. On physical examination, his neck was tender, but he had no neurologic abnormalities. He was sent home from the clinic with advice to take over-the-counter analgesics. Over the next several days, the patient was evaluated for the same or similar symptoms again by his PCP and was seen by the emergency department and urgent care clinics before being admitted to the hospital; however, he was misdiagnosed with Staphylococcal meningitis, and it was not until his third inpatient day when cervical magnetic resonance imaging (MRI) showed a spinal epidural abscess. The commentary discusses the multiple factors leading to erroneous interpretation tests for spinal epidural abscess and the importance of broadening differentials and avoiding premature closure during diagnosis.
A 52-year-old man complaining of intermittent left shoulder pain for several years was diagnosed with a rotator cuff injury and underwent left shoulder surgery. The patient received a routine follow-up X-ray four months later. The radiologist interpreted the film as normal but noted a soft tissue density in the chest and advised a follow-up chest X-ray for further evaluation. Although the radiologist’s report was sent to the orthopedic surgeon’s office, the surgeon independently read and interpreted the same images and did not note the soft tissue density or order any follow-up studies. Several months later, the patient’s primary care provider ordered further evaluation and lung cancer was diagnosed. The commentary discusses how miscommunication contributes to delays in diagnosis and treatment and strategies to facilitate effective communication between radiologists and referring clinicians.
Beginning in her teenage years, a woman began "feeling woozy" after high school gym class. The symptoms were abrupt in onset, lasted between 5 to 15 minutes and then subsided after sitting down. Similar episodes occurred occasionally over the following decade, usually related to stress. When she was in her 30s, she experienced a more severe episode of palpitations and went to the emergency department (ED). An electrocardiogram (ECG) was normal and she was discharged with a diagnosis of stress or possible panic attack. She continued to experience these symptoms for two more years and her primary care physician (PCP) suggested that she see a psychiatrist for presumed panic attacks. At the patient’s request, the PCP ordered a 24-hour Holter monitor, which was normal. When she was 40 years old, the patient experienced another severe episode and went to the ED. During an exercise treadmill test, she experienced another “woozy” spell and the ECG showed an elevated heart rate with narrow QRS complexes. She was diagnosed with paraoxymal supraventricular tacycardia (PSVT). The commentary discusses the diagnostic challenges of PSVT and approaches to reduce diagnostic uncertainty, especially given gender bias in attributing palpitations to psychiatric rather than cardiac causes.
A 71-year-old frail, non-ambulatory woman presented to the emergency department with fever, sweating and dry cough. Her work-up included non-specific evidence of infection but two negative COVID-19 tests. No source of infection was identified, and she was discharged home after three days. During a video visit with her primary care provider the next day, the patient noted worsening symptoms as well as a skin breakdown on her “backside”; however, no rectal or genital exams were completed during her inpatient stay and the physician did not visualize the area during the video visit. The patient was readmitted to the hospital two days later in septic shock due to a necrotizing soft tissue infection related to a perirectal abscess. The commentary discusses the need for a broad differential diagnosis in seriously ill patients, the influence of diagnostic biases during a pandemic, and how to address perceived limitations in the ability to examine patients in the setting of virtual care.
After a breast mass was identified by a physician assistant during a routine visit, a 60-year-old woman received a diagnostic mammogram and ultrasound. The radiology assessment was challenging due to dense breast tissue and ultimately interpreted as “probably benign” findings. When the patient returned for follow-up 5 months later, the mass had increased in size and she was referred for a biopsy. Confusion regarding biopsy scheduling led to delays and, 7 months after initial presentation, the patient was diagnosed with invasive breast cancer involving the axillary nodes and spine. The commentary discusses the diagnostic challenges of potentially discordant findings between imaging and physical exams and the importance of structured inter-professional handoffs and closed-loop referrals in reducing diagnostic delays and associated harm.