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EN4.{1-2,5,9} | Ear Symptoms and External Ear Disorders — PBL Case

CLINICAL SETTING

It is October. Dr Ananya Krishnan, a final-year ENT resident, is covering the Emergency ENT assessment unit at a regional teaching hospital when she is called to see Mr Ramachandran, a 68-year-old retired government clerk who has come in accompanied by his anxious son. Mr Ramachandran has had poorly controlled type 2 diabetes for fifteen years and has recently been started on insulin. The son explains: 'He has had right ear pain for three weeks. His GP gave him antibiotic drops for swimmer's ear and told him it would settle. But the pain has become unbearable — he can't sleep. He is now getting a strange pain in his cheek and we think he has developed some facial weakness this morning.' Mr Ramachandran's GP notes show: right otitis externa diagnosed three weeks ago, topical gentamicin drops prescribed, reviewed once with 'some improvement in canal erythema' noted. HbA1c at his last appointment was 9.8%. On examination in the ENT unit, Mr Ramachandran is distressed and febrile (38.4°C). His right ear shows oedematous EAC skin, purulent discharge, and — on careful examination with suction clearing — granulation tissue and exposed cartilage at the bony-cartilaginous junction of the EAC floor. Facial nerve function reveals a right lower motor neuron facial palsy (House-Brackmann Grade II).

Trigger 1: Recognise and Respond

Dr Ananya reviews the case: Mr Ramachandran's vital signs are stable (BP 146/88, RR 18, SpO2 98%, Temp 38.4°C). Blood tests are sent: WBC 14.2×10⁹/L (neutrophilia), ESR 118 mm/hr, CRP 84 mg/L, blood glucose 18.6 mmol/L, HbA1c 9.8%. Ear swab microscopy shows gram-negative bacilli. He has a right lower motor neuron facial palsy (House-Brackmann Grade II — mild palsy with complete eye closure possible). HRCT of the temporal bone has been requested. The son asks: 'Could this be cancer? Why did the drops not work? Should his GP have done something differently?'

DISCUSSION POINTS

  • Based on the clinical findings (granulation tissue, EAC floor bone/cartilage exposure, elderly diabetic, facial palsy, elevated ESR), what is the diagnosis? Name THREE clinical or investigation criteria that distinguish this from ordinary severe otitis externa.
  • Why does poorly controlled diabetes specifically predispose to this condition? Explain the pathophysiological link between hyperglycaemia, neutrophil function, and Pseudomonas aeruginosa invasion through the EAC.
  • The GP treated this as uncomplicated otitis externa for three weeks. At what point should the clinical picture have prompted reassessment and specialist referral? What 'red flag' findings would have signalled that standard topical therapy was insufficient?
  • Mr Ramachandran's son asks if this could be ear cancer. How would you differentiate malignant OE from squamous cell carcinoma of the EAC in terms of clinical history and investigation findings?
Click to reveal Trigger 2: Investigation, Diagnosis and Management (discuss previous trigger first!)

Trigger 2: Investigation, Diagnosis and Management

HRCT temporal bone (day 1): extensive soft tissue density filling the right EAC; erosion of the tympanosquamous suture; early involvement of the petrous apex bone. No intracranial extension yet. Tc-99m bone scan confirms osteomyelitis of the skull base. Ear swab culture: Pseudomonas aeruginosa, sensitive to ciprofloxacin. Infectious disease team is consulted. Mr Ramachandran is admitted for IV ciprofloxacin and intensive glycaemic control (insulin infusion, target BG 6–10 mmol/L). His facial palsy has not worsened. Repeat ESR at 72 hours on treatment: 88 mm/hr (improving). Meanwhile, Dr Ananya receives a separate referral: a 16-year-old boy, Arjun, presenting with left ear discharge for two months. His otoscopy reveals a central perforation of the pars tensa with mucopurulent but non-foul discharge. There is no cholesteatoma visible. He has a 30 dB conductive hearing loss on left pure tone audiometry.

DISCUSSION POINTS

  • Explain the role of each investigation in managing Mr Ramachandran's malignant OE: (i) HRCT temporal bone — what does it show and how does it guide surgical decisions? (ii) Tc-99m bone scan — what does it contribute that CT cannot? (iii) Serial ESR — how is it used to monitor treatment response?
  • The infectious disease team recommends 6–8 weeks of IV/oral ciprofloxacin. Why is prolonged antibiotic therapy necessary? What are the criteria for de-escalation from IV to oral ciprofloxacin?
  • For Arjun's case: classify his CSOM (type, justification), outline the medical management principles for the active discharge phase, and describe when and why surgical intervention (tympanoplasty) would be considered.
  • Compare the management principles for Mr Ramachandran (malignant OE) and Arjun (tubotympanic CSOM): what is the fundamental difference in urgency, systemic involvement, and required follow-up? Construct a comparison table.
Click to reveal Trigger 3: Complications, Communication and the Wax Dilemma (discuss previous trigger first!)

Trigger 3: Complications, Communication and the Wax Dilemma

Day 10: Mr Ramachandran has improved. ESR is 54 mm/hr. His facial palsy has resolved (House-Brackmann Grade I). He is switched to oral ciprofloxacin and discharged with outpatient ENT follow-up. His son asks whether the facial palsy damage is permanent and what to expect at home. He also asks whether Mr Ramachandran will need surgery. In a separate consultation that afternoon, Dr Ananya sees Mrs Devi, a 55-year-old woman with bilateral hearing loss. On examination, she has bilateral impacted cerumen. She reports a history of left tympanic membrane perforation repaired 8 years ago. She mentions the last person who tried to syringe her left ear caused severe pain and she later developed otitis media. She asks: 'Can you just syringe both ears and let me go home — I have a train to catch?'

DISCUSSION POINTS

  • Counsel Mr Ramachandran's son about the prognosis of his facial palsy: what does House-Brackmann Grade I at 10 days indicate about neural recovery? When is surgical decompression of the facial nerve indicated in malignant OE, and has that threshold been met here?
  • The son asks when surgery is needed for malignant OE. Outline the specific surgical indications in this condition and explain why most cases are managed medically with surgery reserved for defined failures.
  • Mrs Devi wants both ears syringed today. As her clinician, you cannot syringe the left ear. Walk through your reasoning: (i) state the contraindication and explain why syringing is dangerous with a perforation history, (ii) describe the safe alternative method for the left ear, and (iii) explain how you would communicate this to a patient who is impatient and challenging your clinical judgment.
  • Synthesise the learning from all three cases in this PBL session: what is the single most dangerous 'clinical blind spot' that ran through all three cases (Mr Ramachandran's initial GP management, Arjun's delayed referral, and Mrs Devi's request to override contraindications)? How would you design a patient safety checklist for a general practitioner managing ear complaints?

Group Task Assignments

Group 1: Malignant OE: Diagnosis and Pathophysiology

  • Prepare a diagnostic criteria checklist for malignant (necrotising) otitis externa that a GP could use to identify patients requiring urgent ENT referral
  • Explain the pathophysiology: why does Pseudomonas aeruginosa invade through the EAC floor specifically, and what do the fissures of Santorini have to do with it?
  • Identify the most common cranial nerves affected in malignant OE (in order of frequency) and explain the anatomical route of spread that puts each nerve at risk

Competencies: EN4.2

Group 2: CSOM: Classification, Investigation and Surgical Decisions

  • Construct a comparison table of tubotympanic vs atticoantral CSOM covering: perforation site, discharge character, associated pathology, complications, and management
  • Describe the role of HRCT temporal bone in cholesteatoma: what specific features does it look for and how does the report change surgical planning?
  • Explain why cholesteatoma (atticoantral CSOM) is called 'unsafe' — what is the biochemical mechanism of bone erosion and which structures are at risk in approximate order of proximity?

Competencies: EN4.5

Group 3: Wax Removal: Technique, Safety and Contraindications

  • List all contraindications to ear syringing and, for each, explain the mechanism of harm that the contraindication is intended to prevent
  • Describe the step-by-step procedure for safe ear syringing: positioning, water temperature, water pressure, auricle retraction, stream direction, and post-procedure otoscopy
  • Compare and contrast the three methods of wax removal — syringing, micro-suction, and dry instrumentation — in terms of indications, advantages, disadvantages, and equipment needed

Competencies: EN4.9

Group 4: Referred Otalgia and Tuning-Fork Test Interpretation

  • Map the five neural pathways of referred otalgia: for each nerve, name the nerve, the structure it supplies, and give a clinical example of a pathology that could cause referred ear pain via that route
  • Explain the Rinne and Weber test interpretation in detail: what does Rinne positive/negative mean, where does Weber lateralise in conductive vs sensorineural hearing loss, and what is the mechanism explaining each direction?
  • Design a structured otalgia assessment protocol for a non-specialist setting (GP/A&E): when is the diagnosis 'primary otalgia', when is it 'referred otalgia', and what are the red flags that mandate urgent ENT referral?

Competencies: EN4.1

Group 5: Communication and Patient Safety

  • Draft a brief discharge counselling summary for Mr Ramachandran and his son: what does his recovery from facial palsy mean, what medications must he continue, what warning signs should prompt immediate re-attendance, and what follow-up is required?
  • Role-play the conversation with Mrs Devi: she is insisting on bilateral syringing before her train. Draft the exact words Dr Ananya would use to explain the contraindication, offer the safe alternative, and manage her frustration without being dismissive
  • Reflect on the GP's initial management of Mr Ramachandran's malignant OE: what audit criteria could be used to identify similar delayed diagnoses at primary care level, and what system-level changes would reduce the delay?

Competencies: EN4.1, EN4.2, EN4.9

Learning Issues

Research these questions and bring your findings to the discussion.

  1. [EN4.1] What are the five cranial nerve pathways responsible for referred otalgia? For each pathway, name the nerve, the structures it innervates, and give one clinical condition that produces referred ear pain via that route.
  2. [EN4.1] Describe the Rinne and Weber tuning-fork tests: the technique, correct interpretation in conductive vs sensorineural hearing loss, and common pitfalls (false-negative Rinne in severe unilateral SNHL).
  3. [EN4.1] What is the clinical triad of Meniere's disease? How does it differ from BPPV and vestibular neuritis in terms of onset, duration, associated symptoms, and examination findings?
  4. [EN4.2] Define malignant (necrotising) otitis externa: what is the causative organism, the predisposing host factors, the hallmark clinical finding, and the management approach (medical and surgical indications)?
  5. [EN4.2] What is the clinical spectrum of otitis externa? Compare acute diffuse OE (swimmer's ear), chronic OE, otomycosis, and furunculosis in terms of appearance, organism, and treatment.
  6. [EN4.5] Explain the CSOM classification: tubotympanic vs atticoantral type. For each, state the perforation location, associated pathology, complication profile, and management principle.
  7. [EN4.5] What are the stages of acute suppurative otitis media? Which stage is the indication for myringotomy, in which quadrant is the incision made, and which structures are at risk in other quadrants?
  8. [EN4.9] What are the indications, contraindications, and technique for ear syringing for wax removal? What are the safe alternative methods when syringing is contraindicated, and what pre-procedure history is mandatory?