From the Guidelines
The appropriate workup for a patient with intermittent diaphoresis during the day should begin with a thorough history and physical examination to identify potential underlying causes, focusing on timing of episodes, triggers, associated symptoms, medication use, and family history. This approach is crucial as diaphoresis can be a symptom of various conditions, including hyperthyroidism, diabetes, infections, malignancies, neurological disorders, or medication side effects.
Initial Evaluation
The history should aim to identify signs/symptoms of adrenal hormone excess, adrenal malignancy, and/or extra-adrenal malignancy 1.
- Laboratory tests should include:
- Complete blood count
- Comprehensive metabolic panel
- Thyroid function tests (TSH, free T4) as suggested by 1 for patients on immune checkpoint inhibitor therapy, which can cause thyroid dysfunction
- Fasting glucose
Specific Considerations
If pheochromocytoma is suspected based on symptoms such as episodic hypertension, tachycardia, or palpitations, 24-hour urine collection for metanephrines and catecholamines or plasma metanephrines should be ordered 1. For suspected hypoglycemia, a 72-hour fast with glucose monitoring may be appropriate.
Additional Testing
Additional testing might include:
- Chest X-ray
- Electrocardiogram
- In some cases, advanced imaging such as CT or MRI if a tumor is suspected
Referral
Referral to an endocrinologist is recommended if the initial workup suggests hormonal causes, such as thyroid dysfunction or adrenal disorders, as these conditions require specialized management 1. Given the potential complexity and the variety of causes for intermittent diaphoresis, a comprehensive and stepwise approach is necessary to ensure that the underlying cause is accurately identified and appropriately treated, thus minimizing morbidity, mortality, and improving quality of life.
From the Research
Workup for Intermittent Sweating
The workup for a patient with intermittent diaphoresis (excessive sweating) during the day involves a thorough evaluation to determine the underlying cause. The following steps can be taken:
- Understand the pattern of sweating to help find the cause, as generalized hyperhidrosis may be due to an underlying systemic disease or medication use, while focal hyperhidrosis is often primary (idiopathic) and triggered by emotional stimuli 2
- Diagnose hyperhidrosis from patient medical history and physical examination, and use focal sweat measurements to substantiate the diagnosis 3
- Assess the impact of living with hyperhidrosis using patient-reported outcome measures 3
Identifying Secondary Hyperhidrosis
To identify secondary hyperhidrosis, the following parameters can be used:
- Fever, impaired general condition, and C-reactive protein (CRP) levels can help distinguish non-inflammatory and undiagnosed hyperhidrosis from other causes 4
- Symptoms' duration over 1 year can reduce the probability of malignancy or infection as the underlying diagnosis 4
- A diagnostic algorithm for the investigation of recurrent sweating can be used to guide the workup 4
Laboratory Tests
Laboratory tests, such as thyroid function tests, may be ordered to rule out underlying conditions that can cause hyperhidrosis. For example:
- Thyroid-stimulating hormone (TSH) is the best and often only test needed to evaluate thyroid function 5
- Other tests, such as free T4 and anti-TPO antibodies, may be ordered in certain cases, but their interpretation requires a good understanding of pituitary-thyroid physiology 5
Rare Causes
In some cases, intermittent sweating can be a symptom of a rare condition, such as pure autonomic failure, which can present with compensatory excessive sweating as an initial manifestation 6