Meningitis

Question 1

What are the bacterial organisms that can cause in meningitis in adults and neonates?

Answer 1

Neisseria meningitidis (meningococcus) 
Streptococcus pneumoniae (pneumococcus) 
In neonates
E. coli
Group B streptococci

Question 2

What are the viruses that can cause meningitis?

Answer 2

Enteroviruses 
-Echoviruses
-Parechoviruses 
-Coxsackie A and   B viruses 
-(Poliovirus-not seen in UK)
Mumps (now very rare due to MMR vaccine) 
Herpes simplex virus

Question 3

What are uncommon organisms that can cause meningitis?

Answer 3

Haemophilus influenzae type b 
Listeria monocytogenes 
Mycobacterium tuberculosis 
Leptospirosis 
Borrelia burgdorferi  (Lyme Disease) 
Mycoplasma pneumoniae 
Cryptococcus neoformans (in AIDS) 
HIV 
Herpes Viruses other than Herpes simplex eg.   Varicella-Zoster virus (VZV) and Epstein-Barr virus (EBV)
Shunt associated meningitis: 10-30% of patients with ventriculo-atrial/ peritoneal shunts develop ventriculitis and meningitis. Coagulase negative staphylococci (eg, Staph. epidermidis) account for half of the infections,

Question 4

What is aseptic meningitis and what are some causes of it?

Answer 4

A syndrome in which the CSF shows an excessive number of lymphocytes and elevated protein. No organism is cultured or detected by any assay. The diagnosis is confirmed by cytological examination of the CSF.
Causes include tumour cells in the CSF (from a variety of neoplasms) producing an excess of lymphocytes and protein in the CSF.

Question 5

What cranial nerve palsies can occur in meningitis?

Answer 5

CN VI, VII or VIII,

Question 6

When are steroids sometimes indicated in meningitis?

Answer 6

Children with H. influenzae meningitis.
In adults with bacterial meningitis.
The case for steroids is strongest in pneumococcal meningitis

Question 7

What are the risk factors for meningitis?

Answer 7

Diabetes Mellitus
Recent head trauma
Alcoholism

Question 8

What signs are seen in meningitis and should be looked for?

Answer 8

Pyrexia
GCS
Skin and conjunctival petechiae
Vasculitis, macular/maculo-papular, purpuric, pruritic or vesicular rashes
Tachycardia or bradycardia
Low blood pressure if septic shock
Cranial nerve palsies
Papilloedema
Kernig’s sign: with the hip flexed, the patient’s leg cannot be straightened due to hamstring spasm in meningism
Flex the neck to attempt to touch the chin to the chest. This is difficult with any degree of neck stiffness

Question 9

What will blood tests show in meningitis?

Answer 9

Blood culture to see organism type
FBC-shows leucocytosis but in severe infection and septicaemia and DIC can get leukopenia which indicates poor prognosis
In suspected DIC, low platelets (thrombocytopaenia), abnormal clotting and increased fibrin degradation products (FDP) will be seen.
U and E and LFTs will show multi organ failure in sepsis

Question 10

What is fulminant meningococcal septicaemia?

Answer 10

startling suddenness of symptoms causing with rapid deterioration in consciousness, fever, septicaemic shock with renal failure, and disseminated intravascular coagulation (DIC). CSF is sterile with little or no increase in white blood cells (i.e. this syndrome is technically not meningitis), but the outcome is generally worse. For this reason, antibiotics should be given by the GP prior to hospitalisation. A purpuric rash is characteristic. This is the Waterhouse Friedrichsen syndrome, where autopsy reveals bilateral adrenal haemorrhages with adrenal ablation/hypoadrenalism.
50% patients die within the first 24 hours

Question 11

What is chronic meningococcaemia?

Answer 11

Uncommon illness that may last weeks or even months with a rash (recurring every 48-72 hours), joint pains, malaise and fever, sometimes complicated by endocarditis. This may be related to serum complement deficiency

Question 12

What clinical and laboratory signs are indicative of a poor prognosis in meningococcal meningitis?

Answer 12

Clinical: Delay in instigation of antibiotic therapy, extremes of age, purpuric lesions, shock with absence of signs of meningitis and hyperpyrexia (rectal temperature > 40oC).
Laboratory: Presence of DIC, metabolic acidosis and absence of polymorph leucocytosis.

Question 13

What are the predisposing factors for streptococcal meningitis?

Answer 13

Pneumonia
Sinusitis
Endocarditis
Head trauma
Alcoholism
Splenectomy

Question 14

What is an organism that can cause meningitis in neonates?

Answer 14

Listeria monocytogenes

Question 15

What two organisms can cause aseptic meningitis?

Answer 15

Spirochaetes such as Borrelia Burgdorfrei and leptospirosis interrogans

Question 16

What is the presentation of fungal meningitis?

Answer 16

Most commonly, there is a subacute onset of symptoms with low grade fever, headache, nausea, lethargy, confusion and abdominal pain. Meningism is less common, although it can develop quickly as the condition progresses.

Question 17

What two presentations are found in neonatal meningitis?

Answer 17

Early onset - within 3 days of birth and associated with prematurity or a difficult or prolonged birth. Marked respiratory distress, bacteraemia and a high mortality (50%) are typical. The organism has usually been acquired at birth from the mother’s genital tract. 2. Late onset - more than one week after birth. The infection is typified by bacteraemia and meningitis but pulmonary involvement is rare. Mortality is 10-20%. The organism may have been spread by cross-infection from other mothers, babies or healthcare workers.