What is the diagnosis and recommended management for a 15-year-old male with a 3-day history of dizziness, nausea, and diarrhea, exacerbated by noodles and spicy foods, with elevated blood pressure (hypertension), and increased allergy symptoms, including nasal congestion with purulent nasal drainage?

Diagnosis: Acute Bacterial Rhinosinusitis with Possible Food Intolerance

This 15-year-old male most likely has acute bacterial rhinosinusitis based on purulent nasal drainage persisting for one week, combined with dizziness and nausea, while the diarrhea represents a separate food intolerance issue (likely to noodles) rather than a systemic infectious process. The blood pressure readings (133/77 and 128/74) are within normal range for adolescents and do not represent true hypertension requiring intervention 1.

Primary Diagnosis: Acute Bacterial Rhinosinusitis

Clinical Reasoning

• Acute bacterial sinusitis is suspected when upper respiratory symptoms persist beyond 10-14 days, but this patient's one-week duration of purulent nasal drainage with systemic symptoms (dizziness, nausea) warrants treatment 1.
• The combination of nasal congestion with purulent nasal drainage correlates with increased likelihood of bacterial disease 1.
• Prominent symptoms include nasal congestion, purulent rhinorrhea, headache (manifesting as dizziness here), and nausea 1.
• The absence of fever does not exclude bacterial sinusitis, as fever is a "less frequent symptom" in acute sinusitis 1.

Recommended Management for Sinusitis

Initiate antibiotic therapy with amoxicillin-clavulanate as first-line treatment for acute bacterial sinusitis 2:

• Amoxicillin-clavulanate is the preferred systemic antibiotic for chronic and acute bacterial rhinosinusitis 2.
• Alternative options include clarithromycin or trimethoprim-sulfamethoxazole if penicillin allergy exists 2.

Add intranasal corticosteroid spray (mometasone furoate, fluticasone propionate, or beclometasone dipropionate) 2:

• Intranasal steroids reduce mucosal inflammation and swelling, which addresses the underlying pathophysiology 2.
• These are cornerstones of disease management for rhinosinusitis 2.

Prescribe nasal saline irrigation 2:

• Isotonic saline nasal lavage helps restore aeration of nasal and sinus mucosa 2.

Consider short-term nasal decongestant (oxymetazoline) for immediate symptom relief, limited to 3 days maximum 2:

• Temporary use can improve sinus aeration 2.
• Critical pitfall: Do not use nasal decongestants beyond several days, as rebound congestion (rhinitis medicamentosa) will occur 3.

Add oral antihistamine (second-generation like desloratadine 5mg daily) to address the "increased allergy symptoms" 3, 4:

• Second-generation antihistamines do not cause sedation 3.
• Desloratadine specifically reduces nasal congestion in addition to other rhinitis symptoms 4.
• Antihistamines show efficacy on runny nose, sneezing, and nasal itch 3.

Secondary Issue: Food-Related Diarrhea

Clinical Reasoning

• The diarrhea occurs twice daily and is specifically exacerbated by noodles and spicy foods, suggesting food intolerance rather than infectious gastroenteritis or anaphylaxis 1.
• This does NOT meet criteria for food-induced anaphylaxis, which requires acute onset (minutes to hours) with multi-system involvement 1.
• The patient's symptoms have been ongoing for 3 days with isolated GI symptoms (diarrhea, nausea) without respiratory compromise, hypotension, or cutaneous manifestations 1.
• Cardiovascular symptoms in anaphylaxis include dizziness with tachycardia and hypotension; this patient's blood pressure is normal and dizziness is better explained by sinusitis 1, 5.

Recommended Management for Diarrhea

Advise strict avoidance of both noodles AND spicy foods 6:

• The patient reports avoiding spicy foods but continues eating noodles—this must stop immediately.
• Food triggers should be completely eliminated, not just reduced.

Recommend oral rehydration with reduced osmolarity ORS (oral rehydration solution) 6:

• Administer 50-100 mL/kg over 3-4 hours for adolescents 6.
• Small, frequent volumes (5-10 mL every 1-2 minutes) if nausea persists 6.

Resume normal age-appropriate diet immediately after rehydration, excluding identified trigger foods 6:

• Early refeeding is recommended rather than withholding food 6.

Do NOT prescribe loperamide or antimotility agents 6:

• Loperamide should NOT be given to patients under 18 years with acute diarrhea 6.

Blood Pressure Assessment

The blood pressure readings of 133/77 and 128/74 are NOT hypertensive for a 15-year-old male 5:

• These readings are within normal range for adolescents.
• The elevated reading during the dizzy episode likely represents anxiety or vasovagal response, not true hypertension.
• The dizziness with normal blood pressure suggests vasovagal presyncope related to dehydration from diarrhea and/or sinusitis-related symptoms, not cardiovascular pathology 5.

Critical Pitfalls to Avoid

Do not dismiss this as "just allergies" without treating the bacterial component 1:

• One week of purulent drainage with systemic symptoms warrants antibiotic therapy.

Do not use nasal decongestants beyond 3 days 3, 2:

• Rebound congestion will worsen symptoms and create dependency.

Do not give loperamide to this adolescent 6:

• Contraindicated in patients under 18 years.

Do not misdiagnose food intolerance as anaphylaxis 1, 5:

• This patient lacks the acute multi-system involvement required for anaphylaxis diagnosis.
• 10-20% of anaphylaxis cases have no cutaneous manifestations, but this patient also lacks respiratory compromise and hypotension 1, 5.

Do not overlook dehydration as a cause of dizziness 6:

• Ongoing diarrhea for 3 days can cause volume depletion leading to presyncope.

Follow-Up Instructions

Return immediately if any of the following develop 1, 6:

• Worsening headache, facial pain, or visual changes (sinusitis complications).
• Bloody diarrhea (requires medical evaluation for possible antimicrobial treatment) 6.
• Inability to tolerate oral fluids or worsening dehydration signs 6.
• Development of respiratory symptoms, urticaria, or hypotension (would suggest anaphylaxis) 1.

Schedule follow-up in 7-10 days to reassess sinusitis symptoms 1:

• If symptoms persist despite antibiotic therapy, consider imaging or referral to ENT.