Tuberculous Meningitis

Tuberculous meningitis is correctly characterized as a meningoencephalitis, as it affects not only meninges but also brain parenchym

Is Myobacterium tuberculosis infection of the membranes and fluid surrounding the brain and spinal cord.

most common in children aged 0 - 4years

In TBM, the signs and symptoms progress slowly over

several weeks and can be divided into 3 stages.

1st stage: 1-2weeks, characterized by nonspecific symptoms such as fever, headache, irritability, drowsiness and malaise.

2nd stage: usually begins more abruptly. Mostcommon features are lethargy, nuchal rigidity, seizures, Kernig (+), Brudzinski (+), hypertonia, vomiting, cranial nerve palsies and other focal neurologic signs.

3rd stage: is marked by coma, hemiplegia or paraplegia, hypertension, decerebrate posturing,

deteriotation of vital signs and eventually death.

HOPI Character of fever Character of fits Neurological symptoms

- Headache / Irritability /Drowsiness Bulging fontanelle (in infant) Associated /predisposing factors

- Rashes (meningococcaemia)- Ear discharge - Head injury

Past H/O- Traveling to Malaria endemic area- Similar illness- H/O fever with fits- Hospitalization - Contact with any TB patient?

Family History - Family H/O of febrile/afebrile convulsion

Immunization history- eg. HiB vaccine, BCG vaccine

Medication history- Current and previous

Insidious onset Low-grade fever Headache Vomiting Subtle personality change

The classic triad of diagnostic signs - nuchal rigidity- sudden high fever- altered mental status

Poor feeding Vomiting Irritability Lethargy Seizures Reduce consciousness

General condition- Vital signs: HR, Pulse, BP, Temperature- Anthropometry- Well /Ill- Alert and conscious?- Any head trauma?- Nutritional status

Ear discharge? Petechiae, purpura rash Bulging Anterior Fontanelle

Neurological examination- Abnormalities of posture- Abnormal movements- Tone- Power- Tendon reflexes- Eye movements- Breathing pattern- Loss of sphincter tone

Meningeal sign- Neck stiffness - Kernig’s sign - Brudzinski’s sign

Pyogenic meningitis Abscess Late syphilis Encephalitis

Blood tests: FBC, erythrocyte sedimentation rate (ESR), blood sugar, U&E, coagulation, blood culture.

Urine microscopy/culture if: age <18 months, complex seizure or no focus of infection found.

Cerebrospinal fluid (CSF)- lymphocytosis : 100-1000/ml

low glucose high protein Spiderweb clot is characteristic of TB

meningitis The acid-fast bacilli may be seen on

CSF smear or in early morning urine samples

Also known as Pirquet test, or PPD test Positive in Mantoux Test. >10mm in duration at 72hours 2 units of purified protein derivative of tuberculin A positive result indicates TB exposure

- 5 mm or more is positive in - An HIV-positive person- Persons with recent contacts with a TB patient

- 10 mm or more is positive in - Recent arrivals (less than five years) from high-

prevalence countries- Injection drug users

- 15 mm or more is positive in - Persons with no known risk factors for TB

Those who are immunologically compromised, especially those with HIV and low CD4 T cell counts, frequently show negative results from the PPD test.

Steroid use, malnutrition and sarcoidosis can also lead to false-negative results, because the immune system needs to be functional to mount a response to the protein derivative injected under the skin.

Chest X-ray- enlarged hilar lymph nodes- pleural effusion- Abnormal, sometimes miliary pattern

CT and MRI- thickening of basal meninges - infarcts - cerebral oedema/hydrocephalus- tuberculomas

General - Monitoring vital signs, conscious- Lowering temperature with antipyretics

Initial therapy: Rifampicin, Isoniazid and Pyrazinamide plus one of (i) Streptomycin or

(ii) Ethambutol

Intensive phase (2 months)- daily Isoniazid, Rifampicin and Pyrazinamide- a 4th drug(either Ethambutol or Streptomycin) is added if initial drug resistance is present or the burden of organisms is high.

Maintenance phase (7-10 months)- Isoniazid and Rifampicin for the remaining 7-10 months- given daily(perferred) or biweekly or thrice weekly

*all intermittent dose regimens must be directly supervised.

Corticosteroids- Indicated for children with TB

meningitis- may be used in children with pleural

effusion, pericardial effusion, severe miliary disease and endobronchial disease.- give steroids only when accompanied

by appropriate antituberculous therapy dose : prednisolone 1-2mg/kg/day for 3-4weeks, then taper over 3-4weeks.

Rifampicin : Hepatitis, orange discolouration of urine and tears, ‘flu-like’ syndrome with intermittent use

Isoniazid : Hepatitis, neuropathy, pyridoxine deficit, agranulocytosis

Ethambutol : Optic neuritis Pyrazinamide : Hepatitis, arthralgia

Tuberculosis prevention and control efforts primarily rely on the vaccination of infants and the detection and appropriate treatment of active cases

Vaccines- BCG

Public health- WHO declared TB a "global health emergency" in

1993, and in 2006, the Stop TB Partnership developed a Global Plan to Stop Tuberculosis that aims to save 14 million lives between its launch and 2015

Prediction of prognosis of TBM is difficultbecause of the protracted course,

diversity of underlying pathological mechanisms, variation of host immunity, and virulence

of M tuberculosis. Prognosis is related directly to the clinical stage at diagnosis.

Cerebral Malaria

the most common complication and cause of death in severe Plasmodium falciparum infection which is transmitted to humans by female Anopheles mosquitoes.

is the leading cause of seizures and encephalopathy

Its risk factors primarily include children <10 years of age; especially living in malaria-endemic areas.

Changes in behaviour Impaired consciousness Jaundice Parasitaemia > 2% Continued vomiting Hyperpyrexia Oliguria Severe metabolic acidosis

Cerebral malaria Pulmonary edema/ARDS Renal failure Haemoglobulinemia Shock Hypoglycaemia Severe anemia (Hb < 5g%)

Sudden onset of convulsions Persistent high fever Severely impaired consciousness Headache Irritability Orthostatic hypotension Myalgia Red blood cell (RBC) sludging that leads

to capillary blockage Hepatosplenomegaly Jaundice Retinal abnormalities

Thick and thin blood films for malaria parasite

Rapid malaria antigen detection test FBC, CRP, Clotting , ABG/lactate U&E, Glucose, Creatinine Blood culture CXR, ECG   CT followed by lumbar puncture

Fluid requirements vary widely; careful fluid management is critical. Haemofilter early if renal failure. Ventilate early if pulmonary oedema.

Consider exchange transfusion in very seriously ill patient if feasible.

Monitor blood lactate and glucose : quinine may cause hypoglycaemia.

Repeated U&E (and ABG if ARDS) Arrange repeated skilled microscopy to

monitor the parasite counts.

There are two components of malaria prevention:

Reduction of exposure to infected mosquitoes

Chemoprophylaxis- necessary for all visitors to and residents of the tropics who have not lived there since infancy

1. Paediatric Protocols 2nd edition2. Illustrated Textbook of Paediatrics 3rd

edition, Lissauer Clayden3. Nelson Essentials of Paediatrics 5th

edition4. Nelson Textbook of Paediatrics 19th

edition5. Oxford handbook of clinical medicine

7th edition