Adult female with a diffuse erythematous rash extending from the breasts to the waist and a blood pressure of 150/79 mmHg—how should I evaluate and manage the rash and hypertension?

Evaluation and Management of Rash from Breast to Waist with Blood Pressure 150/79

The rash requires immediate dermatologic evaluation to rule out serious conditions like erythema multiforme or drug eruption, while the blood pressure of 150/79 mmHg represents Stage 1 hypertension that warrants confirmation with repeat measurements and outpatient follow-up rather than emergency treatment.

Immediate Rash Assessment

Critical Diagnostic Features to Evaluate

• Examine for target-like lesions with concentric zones of color change, which are characteristic of erythema multiforme and typically present symmetrically on extremities but can involve the trunk 1, 2
• Assess lesion duration: Fixed lesions lasting ≥7 days suggest erythema multiforme, while lesions resolving within 24 hours indicate urticaria 1
• Look for mucosal involvement (oral, ocular, genital), as severe mucosal disease may require hospitalization for IV fluids and electrolyte management 1, 2
• Identify vesicles or bullae: Widespread erythematous or purpuric macules with blisters suggest Stevens-Johnson syndrome rather than erythema multiforme 1

Key Historical Elements

• Recent herpes simplex virus infection (most common trigger for erythema multiforme) or Mycoplasma pneumoniae infection 1, 2
• New medications within past 1-3 weeks, particularly antibiotics, NSAIDs, or anticonvulsants 1, 2
• Recent surgical procedures or contact with disinfectants/adhesives, as contact allergens can trigger erythema multiforme-like reactions 3
• History of recurrent similar episodes, suggesting HSV-associated recurrent erythema multiforme 2

Diagnostic Testing for Rash

• Skin biopsy showing massive edema of dermal papillae with sub-epidermal vesicles and individual cell necrosis confirms erythema multiforme 3
• Potassium hydroxide preparation to exclude fungal infection 4
• Consider patch testing if contact dermatitis is suspected, though this should be performed 3 months after resolution 3

Rash Management

Mild Cutaneous Involvement

• Topical triamcinolone acetonide 0.025% ointment twice daily for symptomatic relief 4
• Oral antihistamines (desloratadine 5 mg daily or equivalent) for pruritus 4

Severe or Recurrent Disease

• HSV-associated recurrent erythema multiforme requires prophylactic antiviral therapy to prevent recurrences 1, 2
• Severe mucosal involvement necessitates hospitalization for IV fluids and electrolyte management 1, 2

Critical Pitfall: Do not confuse erythema multiforme with Stevens-Johnson syndrome—the latter requires immediate hospitalization and has significantly higher mortality 1

Blood Pressure Evaluation

Confirm Hypertension Diagnosis

• Obtain at least 2 separate blood pressure measurements after the patient sits quietly for 5 minutes, as single ED measurements may be falsely elevated due to pain or anxiety 5
• Confirm diagnosis with home blood pressure monitoring (≥135/85 mmHg confirms hypertension) or 24-hour ambulatory monitoring (≥130/80 mmHg confirms hypertension) 6
• This BP of 150/79 mmHg does NOT constitute a hypertensive emergency, as there is no evidence of acute end-organ damage (BP >180/120 mmHg required for emergency) 5

Initial Hypertension Workup

Basic laboratory testing 5:

• Fasting blood glucose
• Complete blood count
• Lipid profile
• Serum creatinine with eGFR
• Serum sodium, potassium, calcium
• Thyroid-stimulating hormone
• Urinalysis
• Electrocardiogram

Screen for secondary causes if patient is young (<40 years old) or has resistant hypertension 5:

• Obstructive sleep apnea (snoring, hypersomnolence)
• Primary aldosteronism (muscle cramps, weakness, hypokalemia)
• Renal artery stenosis
• Medication-induced (NSAIDs, which may also be relevant to the rash)

Blood Pressure Management

Pharmacological Treatment

For confirmed Stage 1 hypertension (130-139/80-89 mmHg), initiate two-drug combination therapy immediately rather than monotherapy 6, 7:

• Preferred combination: RAS blocker (ACE inhibitor or ARB) plus dihydropyridine calcium channel blocker 6, 7
• Alternative: RAS blocker plus thiazide/thiazide-like diuretic 6, 7
• Use fixed-dose single-pill combinations to improve adherence 6, 7

Blood Pressure Target

• Target systolic BP of 120-129 mmHg and diastolic <80 mmHg to maximize cardiovascular risk reduction 5, 6, 7
• Minimum acceptable target is <140/90 mmHg if lower targets are not tolerated 5

Lifestyle Modifications (Concurrent with Medications)

• Sodium restriction to <2g/day 6
• Weight management targeting BMI 20-25 kg/m² if overweight 6
• Regular aerobic physical activity 6
• Alcohol limitation to <100g/week 6
• Smoking cessation 6

Follow-Up Timeline

• Recheck BP within 1-3 months after initiating therapy 5, 7
• Monthly follow-up until BP control is achieved 5
• If uncontrolled after 1-3 months on two-drug combination, escalate to three-drug combination (add thiazide diuretic or calcium channel blocker) 7
• If still uncontrolled on three drugs, add spironolactone 25-50 mg daily as fourth agent 5, 7

Critical Pitfall: Poor medication adherence is the most common cause of resistant hypertension—assess compliance at every visit 5, 6

Integration of Rash and Hypertension Management

Consider medication-induced causes: NSAIDs can both cause rashes and elevate blood pressure 5, 1. If the patient is taking NSAIDs for pain, discontinue them and use alternative analgesics.

Avoid beta-blockers as first-line antihypertensives unless there are compelling indications (post-MI, heart failure, angina), as they are less effective than other first-line agents 6