(Source: BMJ Best Practice, Feb 2024 — UK/US-oriented; HK-specific notes flagged at bottom)
Typical picture: acute onset (1–2 days), rhinitis (clear or purulent), sneezing, post-nasal drip, sore throat, cough (clear→may become purulent, may be non-productive), headache, malaise (unwell but not exhausted — persistent fatigability suggests alternative cause), myalgia, halitosis, low-grade fever (more common in children; >38°C in an adult suggests influenza), non-specific pharyngeal erythema, nasal mucosal oedema/erythema, non-tender cervical nodes, clear chest.
| Feature | Think about |
|---|---|
| Sore throat is the dominant Sx | GAS pharyngitis/tonsillitis → Centor/FeverPAIN |
| Rhinitis >14 days | Allergic rhinitis |
| Sudden onset + fever/chills/severe myalgia | Influenza / pneumonia |
| Pleuritic pain, copious or bloody sputum | Pneumonia / pleurisy |
| Otalgia | Otitis media |
| Facial pain | Sinusitis |
| Meningism (altered GCS, photophobia, hypotonia, neck stiffness, seizures, tachycardia) | Meningitis — urgent action; Kernig’s/Brudzinski’s present in only a minority |
| Adult fever >38°C | Favours influenza over cold |
| Lower resp signs / non-clear chest | Asthma/COPD exacerbation, pneumonia; in kids: bronchiolitis, croup |
| Symptoms persisting >2 weeks | Reconsider Dx |
| Cough >4 weeks | Get CXR |
| Bulging fontanelle + high-pitched cry (infant) | Consider meningism |
| Condition | Distinguishing clues | Confirmatory test |
|---|---|---|
| Allergic rhinitis | Chronic/fluctuating, allergen-triggered/seasonal; sore throat argues against it; other atopy | Skin patch testing, specific IgE |
| Strep tonsillitis | <15yo, tonsillar swelling/exudate, tender anterior cervical nodes, high fever, absence of cough | Throat culture / rapid strep Ag; use Centor/FeverPAIN to decide |
| Acute (GAS) pharyngitis | Same demographic/pattern as tonsillitis; contact with GAS case | As above |
| Scarlet fever | Age 1–10 (rare <1 or adult), GAS contact, scarlatiniform rash, strawberry tongue, no cough/coryza | Usually clinical; rapid Ag or culture/PCR if needed |
| Chronic sinusitis | Symptoms >6 weeks, hyposmia/anosmia; more inflammatory than infective in adults | Sinus CT (abnormal) |
| Acute sinusitis | Reproducible pain on percussion of frontal/maxillary sinus + dental pain + failure of decongestant response; discoloured discharge | Clinical Dx; CT if chronic/atypical |
| Infectious mononucleosis | Marked fatigue, lymphadenopathy, hepatosplenomegaly, maculopapular rash (esp. after amoxicillin) | Monospot/heterophile Ab (80–90% sensitive, may be false-neg early); EBV serology |
| Seasonal influenza | Abrupt onset, fever >38°C, severe myalgia/headache/malaise — more systemic; longer absenteeism; can be severe in elderly/immunocompromised | Viral culture, DFA, RT-PCR |
| COVID-19 | Significant clinical overlap; fever less common in cold vs COVID; headache/rhinorrhoea/myalgia/sore throat more common in cold | RT-PCR / rapid Ag |
| Avian influenza H5N1/H7N9 | Typical flu features + community exposure to circulating virus or travel to affected area — relevant given HK surveillance context | Specialist RT-PCR (upper resp specimen for H7N9; lower resp less likely false-neg) |
| Pertussis | Initial URTI Sx → weeks later paroxysmal cough, inspiratory whoop, post-tussive vomiting ± inspiratory stridor | Bordetella pertussis PCR/culture from NP swab |
| RSV infection | Mainly infants <6mo, prematurity/comorbidity, winter outbreaks, ↑WOB/wheeze/apnoea/poor feeding | PCR |
| Diphtheria (rare but “must-not-miss”) | Travel/exposure to endemic area; sore throat + low fever → dysphagia/dysphonia/dyspnoea/croupy cough; grey-brown pseudomembrane over tonsils/pharynx; bull-neck from lymphadenopathy | Microscopy/culture from beneath pseudomembrane |
| Meningococcal disease | Triad tachycardia + hypotension + high fever; petechial rash, thirst, resp distress, meningism as illness progresses | N. meningitidis isolation from sterile site (blood/CSF/joint) |
| HIV seroconversion illness | Glandular-fever-like: fever, malaise, myalgia, pharyngitis, headache, diarrhoea, lymphadenopathy, maculopapular rash, mucocutaneous ulceration; ~2–4wks post-exposure, resolves ~2wks | Consider in risk context; HIV serology/PCR |
Centor criteria (1 point each): tonsillar exudate, tender anterior cervical lymphadenopathy, fever >38°C, absence of cough - McIsaac modification adds age: +1 (age 3–14), 0 (age 15–44), −1 (age ≥45) - Score 0–1: no testing/antibiotics; 2–3: consider throat swab/rapid Ag; 4–5: empirical antibiotics reasonable
FeverPAIN (1 point each): Fever in past 24h, Purulence, Attend rapidly (≤3 days of Sx), severely Inflamed tonsils, No cough/coryza - 0–1: ~13–18% strep — no antibiotic - 2–3: ~34–40% strep — consider delayed prescription - 4–5: ~62–65% strep — consider immediate antibiotic
Reassurance/expectation-setting (high-yield — patients often expect antibiotics): - Self-limiting; most symptoms resolve 7–10 days - Cough is the most persistent symptom — mean duration ~15.3–28.6 days across studies; paediatric cohort: 26% still symptomatic day 7, 6% at day 14 - Empathic consultation style correlates with better perceived recovery and biochemical markers in trials
Symptomatic treatment — doses (know these; formulary/brand may vary — always check local formulary):
| Drug | Adult dose | Paediatric dose | Notes |
|---|---|---|---|
| Paracetamol | 500–1000mg PO q4–6h PRN, max 4000mg/day | 15mg/kg PO q4–6h PRN, max 75mg/kg/day | Helps fever/pain ± congestion/rhinorrhoea; not sore throat/malaise/cough |
| Ibuprofen | 200–400mg PO q4–6h PRN, max 2400mg/day | ≥6mo: 5–10mg/kg PO q4–6h PRN, max 30mg/kg/day | NSAIDs help discomfort, not resp symptoms |
| Naproxen | 250–500mg PO BD PRN, max 1250mg/day | — | |
| Aspirin | 300–600mg PO q4h PRN, max 4000mg/day | Avoid <18yo (Reye’s syndrome) | Effective for pain/fever, small ↑dyspepsia risk |
| Oxymetazoline nasal 0.05% | 1–2 sprays/nostril BD–QID PRN | ≥6yo: same | Max 3–7 days (rebound congestion / rhinitis medicamentosa) |
| Ipratropium nasal 0.06% | 2 sprays/nostril TDS–QID PRN | 6–11yo: 2 sprays/nostril TDS PRN | Helps rhinorrhoea, not congestion; SEs: dry mouth, epistaxis, nasal dryness |
| Cetirizine/pseudoephedrine combo | 5mg/120mg (1 ER tab) PO BD PRN | ≥12yo: same | Pseudoephedrine caution: avoid in severe/uncontrolled HTN or severe renal impairment — rare risk of PRES/RCVS |
Nasal symptoms (non-drug): humidifier/vaporiser/steam; saline drops/spray (low-quality evidence, reasonable esp. in children); rubber suction bulb in infants.
Cough: - Honey (age ≥1yr): modest evidence — beats no treatment/placebo/diphenhydramine, not better than dextromethorphan; don’t give <1yr (botulism risk) or dextromethorphan <2yr - OTC antitussives/expectorants/mucolytics: no good evidence either way; ACCP explicitly recommends against OTC cough/cold meds - Avoid codeine/opioid-containing cough meds ≤18yo (resp depression, misuse, death risk > benefit) - Pholcodine — withdrawn from EU/UK market (precautionary): linked to rare anaphylaxis to neuromuscular blocking agents (NMBAs) used in GA, if pholcodine used in preceding 12 months. ALPHO case-control study: risk ~1 per 10,000 procedures; risk may persist up to 3 years. Practical point: ask about pholcodine use before any GA with NMBAs; advise patients to stop and switch alternatives. - Vapour rubs: some evidence for symptomatic relief - Inhaled corticosteroids: insufficient evidence for routine use
Antibiotics: NOT recommended — ineffective even with purulent discharge; drives resistance without benefit.
Supplements (largely disappointing evidence — useful to know exact numbers for MRCGP-style critical appraisal questions): - Vitamin C: no benefit on incidence; routine supplementation has minimal/no effect on duration; therapeutic high-dose at onset (on top of routine supplementation) may shorten duration/confinement and ease some symptoms — but evidence is mixed - Vitamin D: deficiency associated with longer illness duration in some studies, but supplementation trials (including high-dose) do not prevent URTI - Zinc: reduces cold duration by ~2.25 days vs placebo in healthy adults (low-quality evidence); may prevent up to half of episodes in children <10yo in low-zinc-prevalence settings only — not replicated in healthy adults - Echinacea: inconclusive for both prevention and treatment - Probiotics (emerging): may ↓URTI episodes/duration/antibiotic use/school absence but low/very-low quality evidence, more GI side effects - No evidence for facemasks in prevention (Cochrane)
Safety-net: return if symptoms >2 weeks, high/persistent fever, worsening trajectory, new focal signs (facial pain, otalgia, pleuritic chest pain, SOB), signs of secondary bacterial complication.
| Complication | Timeframe | Likelihood | Clinical detail |
|---|---|---|---|
| Otitis media | Short-term | Medium | Fever+pain in young children, localised ear pain in older children; purulent MEE; TM loses landmarks with characteristic “bagel/doughnut” appearance (pathognomonic of positive pressure) |
| Acute sinusitis | Variable | Medium | Suspect after ~2 weeks of nasal congestion/post-nasal drip/cough/headache/facial pain; reproducible pain on percussion of frontal/maxillary sinuses + dental pain + decongestant failure → strongly suggests bacterial cause |
| Asthma exacerbation | Short-term | Low | Progressive SOB/wheeze/cough/chest tightness; treat with bronchodilators + corticosteroids |
| Bronchospasm | Variable | Low | Dyspnoea, wheeze, cyanosis, cough; too breathless to speak; silent chest + tachycardia in severe cases; antibiotics not indicated; O2/nebulised beta-agonists if severe |
| Community-acquired pneumonia | Variable | Low | In elderly/immunocompromised, spread from URT can become life-threatening |
| COPD exacerbation | Variable | Low | Triggered by bacterial/viral pathogens or pollutants; acute sustained worsening of resp Sx and function |
This document is BMJ Best Practice, UK/US-oriented (NICE, CDC, ACP). The core evidence base (self-limiting, symptomatic care, no antibiotics, delayed-prescription as a stewardship tool) is internationally consistent and should transfer directly to HA/local primary care practice. I don’t have a verified HA-specific common cold protocol to cite for granular specifics (exact local formulary options, HA’s own antibiotic stewardship targets/wording) — if an OSCE station references local guidelines specifically, check HA GOPC/CKC guidance directly rather than assuming NICE thresholds apply verbatim. Avian influenza (H5N1/H7N9) surveillance context is genuinely more locally relevant in HK than this UK-authored document reflects — worth cross-checking with CHP guidance if it’s likely to come up in your rotation.