D.D.:
A. INFECTIOUS CAUSES OF ACUTE MENINGITTIS
- VIRAL MENINGITIS (ASEPTIC MENINGITIS)
ENTEROVIRUSES, ARBOVIRUSES, HIV , HSV-1 & 2 ,LYMPHOCYTIC CHORIOMENINGITIS VIRUS, MUMPS, ADENOVIRUS, CYTOMEGALO VIRUS, EPSTEIN BARR VIRUS , INFLUENZA A & B , MEASLES, PARAINFLUENZA, RUBELLA & VERICELLA ZOSTER VIRUS.
- BACTERIAL MENINGITIS LIKE MENINGOCOCCAL, PNEUMOCOCCAL, L.MONOCYTOGENES, STAPHYLOCOCCAL & GRAM NEGATIVE BACILLARY MENINGITIS
B. INFECTIOUS CAUSES OF CHR MENINGITIS
1. COMMON BACTERIAL CAUSES
- PARTIALLY TREATED SUPPURATIVE MENINIGITIS
- PARAMENINGEAL INFECTION
- MYCOBACTERIUM TUBERCULOSIS
- LYME DISEASE ( BORRELIA BURGDORFERI )
- SYPHILIS ( SEC. & TERTIARY )
2. UNCOMMON BACTERIAL CAUSES
- ACTINOMYCES
- NOCARDIA
- BRUCELLA
- WHIPPLES DISEASE ( TROPHEREMA WHIPPELII )
3. RARE BACTERIAL CAUSES
- LEPTOSPIROSIS
- PSEUDOALLESCHERIA BOYDII
4. FUNGAL CAUSES
- CRYPTOCOCCUS NEOFORMANS
- COCCIDIOIDES IMMITIS
- CANDIDA SAPROPHYTES
- HISTOPLASMA CAPSULATUM
- BLASTOMYCES DERMATITIDIS
- ASPERGILLUS SP.
- SPOROTHRIX SCHENCKII
5. RARE FUNGAL CAUSES
- CLADOPHIALOPHORA BANTIANA
- CURVULARIA
- DRECHSLERA
- MUCOR
6. PROTOZOAL CAUSES
- TOXOPLASMA GONDII
- TRYPANOSOMIASIS
- ACANTHAMOEBA SP. ( RARE )
7. HELMINTHIC CAUSES
- CYSTICERCOSIS
- GNATHOSTOMA SPINIGERUM
- ANGIOSTRONGYLUS CANTONENSIS
- BAYLISASCARIS PROCYONIS
- TRICHINELLA SPIRALIS ( RARE )
- ECHINOCOCCUS ( RARE )
- SCHISTOSOMA SP. ( RARE )
8. VIRAL CAUSES
- MUMPS
- LYMPHOCYTIC CHORIOMENINGITIS
- ECHOVIRUS
- HIV ( ACUTE RETROVIRAL SYNDROME )
- HERPES SIMPLEX
C. NONINFECTIOUS CAUSES OF CHR MENINIGITIS
- MALIGNANCY (CARCINOMATOUS MENINGITIS)
- CHEMICAL COMPOUNDS
- PRIMARY INFLAMMATION LIKE * SARCOIDOSIS
* VOGT-KOYANAGI-HARADA SYNDROME
* ISOLATED GRANULOMATOUS ANGIITIS OF THE NERVOUS SYSTEM
* SYSTEMIC LUPUS ERYTHEMATOSUS
* BEHCETS SYNDROME
* CHR BENIGN LYMPHOCYTIC MENINGITIS
* MOLLARET RECURRENT MENINIGITIS
* DRUG HYPERSENSITIVITY
* WEGENER GRANULOMATOSIS
- OTHERS LIKE
* MULTIPLE SCLEROSIS
* SJOGRENS SYNDROME
* RARER FORMS OF VASCULITIS ( COGANS SYNDROME )
LABORATORY
β’ CSF pleocytosis - usually predominantly mononuclear but may show more polys early on
β’ CSF cell count up to 3000-4000, but usually 50-200
β’ CSF - increased pressure
β’ CSF - serum antiviral antibody
β’ Elevated CSF protein, but usually < 150 mg/dL (< 1500 mg/L)
β’ CSF sugar usually normal (exceptions - herpes, mumps)
β’ Negative CSF Gram stain and culture for bacteria
β’ Negative CSF latex agglutination or CIEP for bacterial antigens
β’ Normal or mildly elevated WBC (blood)
β’ Viral cultures and/or antibody titers are seldom helpful
OTHER TESTS :
* BLOOD EXAMI & BLOOD CULTURE TO ISOLATE INFECTIVE ORGANISM
* CSF - LYMPHOCYTIC PLEOCYTOSIS( 25-500 ), NORMAL OR SLIGHTLY ELEVATED PROTEINS, NORMAL GLUCOSE & NORMAL OR SLIGHTLY ELEVATED CSF PRESSURE.
* PCR TEST - FOR HSV - 1 & 2 , ENTERO VIRUS, CYTOMEGALO VIRUS ETC.
* CSF CULTURE & OTHER SOURCES FOR VIRUS ISOLATION LIKE THROAT SWAB, SPUTUM, STOOL, URINE & BLOOD.
* SEROLOGICAL STUDIES - NOT DIAGNOSTIC
* ANTIVIRAL ANTIBODIES CAN BE MEASURED IN CSF BY AGAROSE ELECTROPHORESIS REVEALING PRESENCE OF OLIGOCLONAL BANDS.
IMAGING
β’ CT scan or MRI scan of the brain
β’ Usually CT or MRI performed prior to lumbar puncture
DIAGNOSTIC PROCEDURES Lumbar puncture