Differential Diagnosis

• Single most likely diagnosis:
  • Acute rhinosinusitis (viral or bacterial): The patient's symptoms of yellow/green mucus, facial pressure, and productive cough with yellow/green phlegm are consistent with acute rhinosinusitis. The rapid progression of symptoms and the presence of purulent discharge suggest a possible bacterial component, but the initial improvement and subsequent recurrence of symptoms could also indicate a viral etiology or a secondary bacterial infection.
• Other Likely diagnoses:
  • Viral upper respiratory tract infection: The patient's symptoms of sore throat, cough, and nasal congestion could be indicative of a viral upper respiratory tract infection, which could have led to a secondary bacterial sinusitis.
  • Allergic rhinitis: The patient's history of using Allegra and Dymista, as well as the presence of mucosal thickening on the sinus CT, suggests underlying allergic rhinitis, which could be contributing to the patient's symptoms.
  • Sinusitis exacerbation: The patient's history of recurring acute rhinosinusitis episodes and the presence of mucosal thickening on the sinus CT suggest that the current episode could be an exacerbation of underlying chronic sinusitis.
• Do Not Miss diagnoses:
  • Orbital cellulitis: The patient's history of spread to the eye in a previous episode, as well as the current symptoms of sharp pain around the top left side of the nose and left temple, raise concern for orbital cellulitis, which is a serious and potentially vision-threatening complication of sinusitis.
  • Cavernous sinus thrombosis: The patient's symptoms of facial pain and headache could be indicative of cavernous sinus thrombosis, a rare but potentially life-threatening complication of sinusitis.
  • Meningitis: The patient's symptoms of headache and facial pain could also be indicative of meningitis, a serious and potentially life-threatening complication of sinusitis.
• Rare diagnoses:
  • Fungal sinusitis: The patient's history of recurring sinusitis episodes and the presence of mucosal thickening on the sinus CT could suggest fungal sinusitis, although this is a rare diagnosis.
  • Nasal tumor: The patient's history of recurring sinusitis episodes and the presence of a retention cyst on the sinus CT could suggest a nasal tumor, although this is a rare diagnosis.

The patient's decision to discontinue the Augmentin due to side effects and wait for the culture results may have contributed to the development of antibiotic resistance if the culture ultimately shows a bacterial pathogen sensitive to Augmentin. However, the patient's history of sensitivity to medications and the potential risks of antibiotic use, including C. difficile infection, must be weighed against the potential benefits of treatment. If the culture comes back with no growth, the patient's symptoms could still be managed with supportive care, such as nasal saline irrigations, humidification, and pain management, and the patient could be monitored for signs of worsening infection. If the ENT recommends resuming Augmentin or switching to a different antibiotic, the patient's allergy to sulfa drugs and sensitivity to new medications would need to be taken into account.