From the Guidelines
For hypersensitivity in both top feet without other medical history, I recommend starting with a comprehensive foot evaluation, including inspection of the skin, assessment of foot deformities, neurological assessment, and vascular assessment, as outlined in the 2023 standards of care in diabetes 1. This condition may represent peripheral neuropathy or other foot-related issues, and a thorough evaluation is necessary to determine the cause. Begin with simple measures like wearing loose-fitting shoes, avoiding prolonged standing, and using cushioned insoles. For symptom relief, try over-the-counter medications like acetaminophen (500-1000mg every 6 hours as needed) or ibuprofen (400-600mg three times daily with food). Topical options include lidocaine 5% patches or diclofenac 1% gel applied to the affected areas 3-4 times daily. If symptoms persist, prescription medications such as gabapentin (starting at 300mg at bedtime, gradually increasing) or amitriptyline (10-25mg at bedtime) may help manage neuropathic pain. It is also essential to consider the possibility of allergic contact dermatitis (ACD), a type IV/delayed-type hypersensitivity reaction to small environmental chemicals, which can manifest as eczematous lesions on the feet 1. Blood tests should be performed to check for diabetes, vitamin B12 deficiency, thyroid function, and other metabolic causes. Physical therapy focusing on gentle stretching and strengthening exercises can improve circulation and reduce symptoms. The hypersensitivity might be caused by nerve compression, inflammation, or metabolic factors affecting the peripheral nerves, so identifying and addressing the underlying cause is essential for effective treatment. Key aspects of the evaluation and management include:
- Comprehensive foot evaluation
- Neurological and vascular assessment
- Simple measures for symptom relief
- Consideration of ACD and other potential causes
- Blood tests to rule out underlying metabolic causes
- Physical therapy to improve circulation and reduce symptoms.
From the Research
Hypersensitivity Reaction Workup
- The workup for hypersensitivity reactions, particularly those affecting the feet, involves a thorough clinical history and physical examination 2, 3.
- Skin testing and/or blood tests for allergen-specific IgE antibodies may be used to confirm the diagnosis of an allergic disorder 2, 3.
- In vivo provocation tests may be used as secondary confirmatory tests when the clinical history is discordant with primary test results 2, 3.
Bilateral Top Feet Symptoms
- Bilateral numbness and paresthesia in the toes and soles may be symptoms of diabetic symmetric polyneuropathy (DSPN) 4.
- These symptoms, along with disproportional sweating restricted to the face and trunk, are useful for the diagnosis of DSPN 4.
- A decline in foot sole skin sensitivity can occur naturally with aging or as a result of neurological disorders, including peripheral neuropathies 5.
Classification of Hypersensitivity Reactions
- Hypersensitivity reactions can be classified into four types according to pathophysiology, as described by Gell and Coombs 6.
- The classification system has been modified over time to reflect new insights into the mechanisms of these disorders 6.
Clinical Perspectives
- The feet play an important role in sensory mechanisms of postural control, and sensory information from the foot contributes to standing balance 5.
- A decline in foot sole skin sensitivity can lead to poorer postural control and increased risk of falls, particularly in older adults or those with neurological disorders 5.