Your next patient is 19 with a fever and a bad headache since yesterday. Here's how the bacterial meningitis case unfolds and what to pick up on the way.

A bacterial meningitis case can be missed if you stop at “fever and a bad headache since yesterday”. In a 19 year old, that sounds everyday, but the trap is not asking about how fast it evolved and the red flags that often are not volunteered: the worst generalised headache, neck stiffness with painful chin to chest, photophobia, a non blanching purpuric rash on the shins and trunk, and drowsiness or confusion over hours.

This page walks through how the case presents, what to pick up in the history, the bedside glass or tumbler test for a rash that does not blanch, and the investigations. It sets out the teaching points: the fever, headache, neck stiffness and photophobia pattern with reduced consciousness, why a non blanching purpuric rash means meningococcal septicaemia, and how CSF from lumbar puncture distinguishes bacterial from viral disease, plus follow up for hearing loss and prevention with meningococcal vaccination.

How the case presents

Your next patient is 19 with a fever and a bad headache since yesterday. In their own words: "A fever and a bad headache since yesterday."

Observations on arrival:

Observation	On arrival
Heart rate	118 beats per minute
Blood pressure	102/62 mmHg
Respiratory rate	22 breaths per minute
Oxygen saturation	97%
Temperature	39.3 °C

What to pick up in the history

These are the findings the case is built around. Each one moves you towards or away from bacterial meningitis, and the scorecard checks whether you found it.

Severe generalised headache, the worst he has had: sudden severe headache with fever puts bacterial meningitis and subarachnoid haemorrhage at the top of the differential.
Neck stiffness, painful to bend chin to chest.
Photophobia, bright light hurts his eyes: reinforces meningeal irritation and raises the pre-test probability of meningitis over a simple febrile illness.
Non-blanching purpuric rash on shins and trunk.
Drowsy and confused over the last few hours: falling conscious level marks severity, is a contraindication to immediate lumbar puncture and prompts CT and critical care.
Completely well yesterday, onset within hours: hyperacute onset points to bacterial rather than viral or tuberculous meningitis and drives the urgency.
Lives in university halls with other unwell students: crowded student accommodation is classic for meningococcal carriage and triggers notification and contact chemoprophylaxis.
Cold mottled peripheries and a racing heart: indicates septic shock, escalating this from meningitis alone to a sepsis-6 and critical care problem.

Red flags you must not miss

The case marks these as must-elicit. They only come out if you ask.

Non-blanching purpuric rash on shins and trunk.
Drowsy and confused over the last few hours.
He has not had a seizure/fit and has no weakness or numbness down one side and no problem with his speech.

Investigations and what they showed

CSF analysis: Turbid CSF at high opening pressure: markedly raised neutrophils (polymorphs), high protein, low glucose (low CSF:serum ratio). A bacterial (pyogenic) picture.
Gram stain: CSF Gram stain: Gram-negative diplococci, consistent with Neisseria meningitidis (meningococcus).
Blood culture: Neisseria meningitidis isolated.
Full blood count: Neutrophilia with a raised white cell count; platelets falling (early DIC). Why it helps: supports a severe bacterial infection and flags disseminated intravascular coagulation (falling platelets) in meningococcal septicaemia.
C-reactive protein: Markedly raised.
Lactate: Raised.
MRI brain: Post-contrast leptomeningeal (pial) enhancement over the surface of the brain, in keeping with meningitis; no abscess or established complication.
Inspect a rash: Crops of small dark red and purple macules, some pinpoint and some coalescing into larger blotches, which do not fade when a glass tumbler is rolled over them. Why it helps: this is the cardinal sign.
Inspect the calves and shins: Dense showers of pinpoint red-purple petechiae over the shin and calf, with a few darker purpuric spots and one small necrotic-looking lesion. Why it helps: the shins are where the flatmate spotted it with the glass test, and where the rash is usually densest and earliest, always undress the legs of a febrile young adult with headache.
Inspect the hands: Purple-red purpuric macules over the dorsum of the hand and fingers, several already coalescing into larger irregular patches. Why it helps: purpura coalescing beyond pinpoint petechiae signals meningococcal septicaemia with consumptive coagulopathy/DIC and progression towards purpura fulminans, this is the marker of a patient who needs ICU, not just a ward bed.
Inspect the feet: Confluent petechiae and darker purpuric lesions over the ankle and dorsum of the foot, some with a central dusky crust. Why it helps: the rash must be tracked over the whole body surface, including feet and soles, the extent and rate of spread are the crudest but fastest bedside measure of how fast the septicaemia is moving.
Inspect the back: Sparse, easily missed pinpoint petechiae scattered over the skin of the back. Why it helps: trunk lesions are far subtler than those on the legs and are routinely missed unless the patient is fully undressed and examined in good light, one non-blanching spot is enough to act on.
Inspect the thighs: Net-like blue-purple mottling of the skin over the thighs and knees.
Inspect the patient's level of alertness and demeanour: Drowsy but rousable (GCS about 14), answering in short sentences, confused about the time and drifting back to sleep between questions.
Inspect the eyes: He screws his eyes shut and turns his head away from the examination light; the curtains have been pulled closed. Why it helps: photophobia with fever, headache and neck stiffness is the classic meningitic triad, the drawn curtains are often visible before you have said a word.
Inspect the patient's posture and position: He lies very still on his side, neck held rigid and slightly extended, and resists any attempt to flex it. Why it helps: neck stiffness held as a posture rather than elicited as a sign is one of the earliest visual clues to meningism.

Imaging findings

CT head: No mass, midline shift, hydrocephalus or effaced basal cisterns. Normal.
X-ray chest: Clear lung fields, no consolidation. Normal.
X-ray skull: Normal / non-specific, a skull X-ray does not diagnose meningitis.

Why the diagnosis is bacterial meningitis

The decisive diagnosis is bacterial meningitis with meningococcal septicaemia, the rapid fever, severe headache, meningism, photophobia and reduced consciousness in a young adult in halls, plus a non-blanching petechial/purpuric rash and sepsis, with a turbid neutrophilic, high-protein, low-glucose CSF showing Gram-negative diplococci. Calling it 'Viral meningitis' would be a dangerous under-call: the non-blanching rash, sepsis and CSF profile make this bacterial/meningococcal disease. The fully specific label is meningococcal meningitis/septicaemia.

Bacterial meningitis at a glance

What it is

Bacterial meningitis is an infection of the meninges, the membranes covering the brain and spinal cord, caused by bacteria such as Neisseria meningitidis (meningococcus) or Streptococcus pneumoniae. When meningococcus also infects the bloodstream, it causes meningococcal septicaemia, which produces the characteristic non-blanching rash.

Pathogenesis

Bacteria reach the meninges via the bloodstream or from a nearby focus of infection, triggering an intense inflammatory response in the subarachnoid space. This raises intracranial pressure and produces the classic triad of fever, headache and neck stiffness, with photophobia and, as pressure or infection worsens, a falling conscious level. When meningococci invade the bloodstream, they damage the walls of small blood vessels, causing tiny haemorrhages into the skin that do not blanch under pressure, a sign of sepsis, not just meningitis alone.

Who it affects

Bacterial meningitis can affect any age but has peaks in infancy and in adolescents/young adults, particularly those in close-contact settings such as university halls of residence. Neisseria meningitidis and Streptococcus pneumoniae are the leading causes beyond the neonatal period.

How serious it is

Survivors can be left with complications such as sensorineural hearing loss, seizures or neurological deficits, which is why audiology follow-up matters after recovery.

Causes and risk factors

Close-contact living (halls of residence, military barracks), recent respiratory infection, and lack of meningococcal vaccination all raise risk.

Investigations and lab tests

Blood cultures and a full sepsis screen run in parallel.

At a glance: Makes the diagnosis: LP and CSF analysis (turbid, neutrophils, high protein, low glucose).

Teaching points

Bacterial meningitis is a time-critical emergency: fever + headache + neck stiffness + photophobia ± reduced consciousness; a non-blanching purpuric rash means meningococcal septicaemia.
The glass/tumbler test: a petechial or purpuric rash that does not blanch under pressure is meningococcal disease until proven otherwise.
The LP/CSF makes the diagnosis (bacterial = turbid, neutrophils, high protein, low glucose, organisms on Gram stain; viral = lymphocytes, normal glucose), but only after excluding contraindications.
Follow up survivors for complications, especially sensorineural hearing loss (audiology), and promote meningococcal vaccination for prevention.

Practise a similar case

Reading a case is comfortable, asking the right questions in real time is not the same. It feels different to pick up 'worst ever headache' and sudden onset on paper than to tease that out while the 19 year old is drowsy, photophobic and struggling to keep his eyes open. Try taking a history from another acute patient and see how your approach holds up.

Here's one from the same specialty, with the diagnosis left for you to find. Your next patient has had fever, sweats and headache for 5 days after returning from abroad. Take this patient's history in Diagnosica. It's free to start, no card needed.

Bacterial meningitis case presentation: history, findings and tests