What is the most appropriate next step in managing a 78-year-old woman with a red, hot, and swollen right foot, diagnosed with cellulitis (infection of the skin and subcutaneous tissues), given her medical history of coronary artery disease, hypertension, type 2 diabetes mellitus, peripheral neuropathy, and chronic kidney disease (Impaired renal function)?

From the Guidelines

The most appropriate next step in management for this patient is casting and avoidance of weight bearing. This patient is presenting with classic signs of Charcot arthropathy (also called neuropathic arthropathy), which is a progressive condition characterized by joint destruction, dislocations, and deformities. The diagnosis is supported by her history of diabetes with peripheral neuropathy, the presence of unilateral foot swelling after minor trauma, and the absence of significant infection markers in her joint fluid analysis, as indicated by the normal leukocyte count and negative Gram stain 1.

The management of acute Charcot arthropathy primarily involves immobilization with casting and offloading the affected foot to prevent further joint destruction and deformity. This approach allows the acute inflammatory phase to resolve and promotes healing. The patient should remain non-weight bearing on the affected foot until clinical signs of inflammation (redness, warmth, swelling) have resolved, which typically takes several months. After the acute phase resolves, the patient will likely need custom footwear or braces to prevent recurrence and manage any residual deformity. Early recognition and proper offloading are crucial to prevent progression to severe foot deformities that might ultimately require surgical intervention.

Some key points to consider in the management of this patient include:

• The importance of regular foot examination and patient education on healthy foot behaviors, as recommended by the 2016 AHA/ACC guideline on the management of patients with lower extremity peripheral artery disease 1.
• The need for prompt diagnosis and treatment of foot infection, which can be subtle in patients with diabetes mellitus and peripheral neuropathy, and may require referral to an interdisciplinary care team 1.
• The role of imaging studies, such as plain radiographs or magnetic resonance imaging, in evaluating the extent of foot damage and guiding treatment decisions 1.

Overall, the management of this patient requires a comprehensive approach that addresses the underlying causes of her foot symptoms, prevents further complications, and promotes optimal healing and functional outcomes.

From the FDA Drug Label

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From the Research

Diagnosis and Management

The patient's symptoms, including a red, hot, and swollen right foot, along with a history of peripheral neuropathy and type 2 diabetes mellitus, suggest a possible diagnosis of Charcot neuro-osteoarthropathy (CN) 2, 3, 4, 5, 6. The absence of immediate swelling after the trauma and the presence of decreased sensation over both feet, as shown by monofilament testing, further support this diagnosis.

Key Considerations

• The patient's condition is likely a result of underlying neuropathy, trauma, and perturbations of bone metabolism 3.
• Differentiation from acute diabetic foot infection is crucial, and the patient's normal blood leukocytes and negative Gram stain help to rule out infection 4.
• The presence of 200/mm3 red blood cells and 200/mm3 white blood cells (60% neutrophils) in the fluid aspiration from the right tarsus suggests inflammation, which is consistent with CN 2.

Appropriate Next Steps

• Given the likely diagnosis of CN, the most appropriate next step in management would be to provide mechanical protection to the affected foot, usually in an irremovable total contact cast, to prevent further injury and promote healing 2, 4.
• Among the provided options, casting and avoidance of weight bearing is the most appropriate choice, as it aligns with the recommended treatment for CN 2, 4.

Options Analysis

• Option A (Casting and avoidance of weight bearing) is the most appropriate choice, as it is consistent with the recommended treatment for CN 2, 4.
• Option B (Intravenous vancomycin) is not appropriate, as there is no evidence of infection.
• Option C (Orthotic shoe inserts) may be considered in the long term to accommodate any deformity, but it is not the most appropriate next step.
• Option D (Physical therapy) is not relevant to the acute management of CN.
• Option E (Surgical intervention) may be considered in some cases, but it is not the most appropriate next step in this case, as the patient's condition is not severe enough to require immediate surgery 5.