A Clinical Case Report
Author: Nuha Emad Awada
Medical school: Jordan University of Science and Technology (JUST)
Introduction
Diabetes mellitus is a common chronic metabolic disorder characterized by persistent hyperglycemia resulting from inadequate insulin secretion, impaired insulin action, or both. Long-standing hyperglycemia can damage multiple organ systems and lead to microvascular and macrovascular complications.
According to the Centers for Disease Control and Prevention (CDC), an estimated 40.1 million people in the United States had diagnosed or undiagnosed diabetes in 2023. Diabetes is associated with an increased risk of cardiovascular disease, kidney disease, neuropathy, retinopathy, foot ulceration, and lower-extremity amputation.
This case illustrates the potential consequences of prolonged untreated or poorly monitored type 2 diabetes in a patient who had gone approximately five years without routine medical follow-up or recommended screening.
How Chronic Hyperglycemia Causes Complications
Chronic hyperglycemia produces cellular and vascular injury through several interrelated biochemical pathways. Excess intracellular glucose increases activity of the polyol pathway, contributing to sorbitol accumulation, NADPH depletion, oxidative stress, and cellular injury. Hyperglycemia also increases diacylglycerol (DAG) and protein kinase C (PKC) activity, contributing to endothelial dysfunction, altered vascular permeability, and inflammation. Increased flux through the hexosamine pathway can alter protein and gene regulation and contribute to abnormal extracellular matrix deposition. Together, these mechanisms contribute to progressive neurological, vascular, retinal, and renal injury.
Clinical Case Presentation
A 57-year-old Hispanic man with a more than 20-year history of type 2 diabetes mellitus presented to a clinic for a disability evaluation. He reported that he had not attended routine medical follow-up or undergone recommended screening for approximately five years. He attributed his lack of medical care primarily to financial and insurance-related difficulties and hoped that obtaining disability status would provide access to medications, screening, and other medical services.
At presentation, he reported excessive thirst, increased hunger, polyuria, severe fatigue, and blurred vision. He also described longstanding tingling, numbness, and swelling involving both the upper and lower extremities. These sensory symptoms had not previously been formally evaluated or treated.
The patient reported that his last ophthalmologic evaluation had been approximately five years earlier. He also reported a family history of diabetic retinopathy and currently experienced blurred vision.
His diabetic history was complicated by significant lower-extremity disease. In 2024, he developed an ulcer of the great toe that became severely infected and ultimately required amputation of the affected great toe. Subsequently, he developed another ulcer on the plantar surface of the foot. At the time of presentation, he reported that the ulcer was extremely painful and appeared infected. The condition had impaired his mobility, and he walked with a limp.
The patient reported diabetes mellitus in both his maternal and paternal family histories. He acknowledged awareness of the potential complications of diabetes but had continued to defer medical evaluation and treatment.
He described his diet as generally balanced, consisting primarily of protein, vegetables, and fruit, with occasional fast-food consumption. He reported occasional alcohol use, typically one beer. He was a former smoker and reported that he had stopped smoking approximately 17 years earlier. He also reported daily physical activity, including push-ups, sit-ups, and jumping jacks.
The patient worked as a chef at BJ’s and reported prolonged periods of standing. He stated that his feet frequently became wet during work, particularly during cleaning activities at the end of his shift, and that he did not always dry his feet thoroughly afterward. This occupational exposure is clinically relevant in the setting of an active chronic foot ulcer.
He denied known hypertension, hyperlipidemia, sleep apnea, and paroxysmal nocturnal dyspnea. However, his blood pressure was markedly elevated at 184/99 mmHg on presentation and remained elevated at 168/100 mmHg approximately 30 minutes later, raising concern for previously unrecognized or untreated hypertension.
He also reported approximately one year of acid reflux. He stated that his last electrocardiogram had been approximately 20 years earlier and that he had not undergone recent cardiovascular evaluation. His only reported prior surgery was the great-toe amputation in 2024.
Major Diabetes-Related Complications Illustrated by the Case
Peripheral Neuropathy
The patient’s longstanding tingling and numbness of the extremities are concerning for diabetic peripheral neuropathy. Loss of protective sensation can allow minor injuries to go unnoticed and can increase the risk of foot ulceration and infection. Current American Diabetes Association (ADA) guidance recommends assessment for diabetic peripheral neuropathy beginning at the diagnosis of type 2 diabetes and at least annually thereafter.
Diabetic Foot Ulceration and Prior Amputation
The history of a severely infected great-toe ulcer requiring amputation, followed by another plantar foot ulcer, places this patient in a high-risk category for recurrent ulceration and further limb complications. Neuropathy, peripheral arterial disease, foot deformity, prior ulceration, prior amputation, smoking history, and kidney disease can all contribute to diabetic foot risk. The presence of an open ulcer or suspected infection warrants prompt clinical assessment.
Possible Diabetic Retinopathy
Blurred vision after approximately five years without ophthalmologic screening raises concern for diabetic retinopathy or another ocular disorder. Importantly, the case does not establish a diagnosis of diabetic retinopathy because no recent ophthalmologic examination or retinal findings are provided. For people with type 2 diabetes, the ADA recommends a comprehensive dilated eye examination at the time of diagnosis, with subsequent screening intervals determined by retinal findings and individual risk.
Cardiovascular and Vascular Risk
Diabetes substantially increases cardiovascular risk and is associated with peripheral arterial disease and other vascular complications. The patient’s markedly elevated blood pressure on two measurements also raises concern for previously unrecognized or untreated hypertension. The available case information does not establish coronary artery disease or peripheral arterial disease, so these should be considered clinical concerns requiring evaluation rather than confirmed diagnoses.
Possible Kidney Involvement
The case discusses the renal consequences of diabetes in general, but it does not provide laboratory data establishing chronic kidney disease in this patient. Assessment of kidney function and urine albumin excretion would be appropriate when evaluating a person with long-standing type 2 diabetes, particularly when other end-organ complications are present.
Discussion
This case demonstrates how prolonged gaps in diabetes care can allow multiple complications to develop without timely detection or intervention. The patient’s neuropathic symptoms, history of an infected foot ulcer requiring amputation, recurrent plantar ulceration, and visual symptoms are clinically significant. His markedly elevated blood pressure adds another potentially modifiable cardiovascular risk factor.
The case also highlights the importance of access to care. Although the patient reported that he had deferred care partly because of financial and insurance-related difficulties, the clinical consequences illustrate the potential cost of delayed screening and treatment. Early identification and management of hyperglycemia, hypertension, lipid abnormalities, neuropathy, retinopathy, kidney disease, and foot complications can reduce the risk of severe morbidity.
Prevention and Routine Monitoring
- Regular monitoring of glycemic control and individualized glucose-lowering therapy.
- Blood-pressure assessment and treatment when hypertension is confirmed.
- Regular assessment for diabetic kidney disease, including appropriate laboratory testing.
- Routine comprehensive eye examinations and prompt ophthalmologic evaluation when visual symptoms occur.
- At least annual assessment for diabetic peripheral neuropathy and loss of protective sensation, with more frequent evaluation in high-risk patients.
- At least annual comprehensive foot evaluation, with inspection at every visit for patients with prior ulceration or amputation.
- Prompt evaluation of any new foot ulcer, redness, swelling, drainage, pain, or suspected infection.
- Lifestyle measures including a balanced diet, physical activity appropriate to the patient’s medical condition, smoking cessation, and maintenance of a healthy body weight.
Conclusion
Long-standing type 2 diabetes can affect the nervous system, eyes, kidneys, cardiovascular system, and lower extremities. This case illustrates the consequences that may occur when routine follow-up and recommended screening are interrupted for several years. The patient’s sensory symptoms, recurrent foot ulceration and prior amputation, visual complaints, and markedly elevated blood pressure demonstrate the importance of comprehensive diabetes care and early recognition of complications.
Important Clinical Note
This article is intended for educational and informational purposes. It is not a substitute for individualized medical evaluation, diagnosis, or treatment. A patient with an active or suspected infected diabetic foot ulcer, new visual changes, markedly elevated blood pressure, or other concerning symptoms should receive timely professional medical assessment.
References
- Centers for Disease Control and Prevention. National Diabetes Statistics Report. Updated 2026. https://www.cdc.gov/diabetes/php/data-research/index.html
- American Diabetes Association Professional Practice Committee for Diabetes. 12. Retinopathy, Neuropathy, and Foot Care: Standards of Care in Diabetes—2026. Diabetes Care. 2026;49(Suppl 1):S261–S276. https://doi.org/10.2337/dc26-S012
- American Diabetes Association Professional Practice Committee for Diabetes. 10. Cardiovascular Disease and Risk Management: Standards of Care in Diabetes—2026. Diabetes Care. 2026;49(Suppl 1):S216–S260. https://doi.org/10.2337/dc26-S010
- Alila Medical Media. Diabetes Type 1 and Type 2, Animation. YouTube. 2014. https://www.youtube.com/watch?v=XfyGv-xwjlI
- Alila Medical Media. Diabetic neuropathy, animation. YouTube. 2021. https://www.youtube.com/watch?v=CyOdY5L-YeE
- Cleveland Clinic. 10 Early Signs of Diabetes. 2024. https://www.youtube.com/watch?v=wcQCmX8fHW0
- MedlinePlus. Diabetes complications. U.S. National Library of Medicine. https://medlineplus.gov/diabetescomplications.html
- Zhao L, Yuan J, Yang Q, et al. Diabetes and its complications: molecular mechanisms, prevention and treatment. Signal Transduction and Targeted Therapy. 2026;11:22. https://doi.org/10.1038/s41392-025-02401-w
