Friday, May 21, 2010

List: Most common 7 organisms in bacterial meningitis

Streptococcus pneumoniae
Neisseria meningitided
Listeria monocytogenes
Staphylococcus aureus
Haemophilus influenza
Escheria coli
Streptococcus agalactiae

source Lin AL, Safdieh JE.  The Evaluation and Management of bacterial meningitis: current practice and emerging developments.  The Neurologist 2010: 16:143-151.

Sunday, May 16, 2010

The Heidenhain variant of Creutzfeldt-Jakob disease

From Neurology resident/fellow page
The Heidenhain variant of Creutzfeldt-Jakob disease

The Heidenhain variant of Creutzfeldt-Jakob disease presents with isolated visual

symptoms for 2-4 weeks, and these may include disturbed perception of colors or shapes,

visual hallucinations, or cortical blindness with anosognosia (Anton syndrome). The

clinical course of this variant is rapidly progressive. Diagnosis is difficult in the early

stage since the neurological examination is otherwise normal and typical EEG findings

are absent. Visual symptoms may be erroneously attributed to ophthalmologic disease,

which in some cases lead to needless ocular procedures. This is particularly important

since prion particles can be transmitted by ocular tissue. Brain MRI may show the

characteristic cortical ribbon sign with diffusion restriction in the parieto-occipital cortex.

Friday, May 14, 2010

CAPS : A treatable neurologic disorder

Kitley JL, et al. Neurology 2010; 74: 1267-1270
Cryopyrin associated periodic disorder (CAPS) is a  rare disorder that, untreated, will progress to amyloidosis, renal failure and death.  It responds dramatically to anti interleukin 1 therapy with cankinumab.  Authors summarize 13 published cases of CAPS neurologic features, including one case of their own and twelve of the literature. 

-- includes 3 previously thought to be unrelated conditions, which are the Muckle Wells syndrome, familial cold autoinflammatory syndrome (FCAS), and chronic infantile neurologic, cutaneous and articular syndrome (CINCA). 

Presentation of  adult patients with CAPS included
-- Headache in 12/13; migraine like in 10
-- myalgia in 9
-- hearing impairment in 7
-- papilledema in 6
--optic pallor in 2

MRIs were normal
CSF in 1 patient showed high OP and pleocytosis
FCAS presents with fever, rash, and conjunctivitis provoked by cold; is mildest
MWS is more severe with progressive SN deafness, one third developing amyloidosis, nephrotic syndrome and renal failure
CINCA presents in infancy and is most severe
Some have history of aseptic meningitis

All show episodic fever, urticarial like rash, conjunctivitis, flu like symptoms, acute phase response with anemia, high ESR and CRP, and elevated serum amyloid A.

Sunday, May 02, 2010

Nosocomial bacterial meningitis pearls

Van de Beek et al.  NEJM 2010; 362: 146-154.  Current Concepts.  Review article.

1.  Post craniotomy, one third of cases occur in first week, one third in second week, and one third after second week, up to "years" after craniotomy.  The incidence is 0.8-1.5 %.

2.  Internal ventricular catheter infection causes infection 4-17 % of time.  Colonization at time of surgery is the most important cause, and most cases occur within one month.

3.  External ventricular catheter shunts has an 8 % incidence of infection with a sharp rise after five days.  Article suggests no reason to remove a catheter just because 5 days has elapsed.

4.  CHT usually has a basilar skull fracture if infections occur.  This is most common cause of recurrent meningitis.

5.  Gram staining and culture are hallmarks of diagnosis and measurement of cells and diff may be falsely negative in many cases. especially ventricular catheters.

6.  Post neurosurgery, a CSF lactate level of > 4 mmol/L has a sensitivity of 88 %, specificity of 98 %, PPV of 96 %, and a NPV of 94 % for bacterial meningitis.  However, one review suggested many cases would be missed with this cutoff.

7.  Antibiotics postop or post head injury should be vancomycin plus ceftazidine, cefepime, or meropenem.  Goal should be serum trough of 15-20 for vancomycin.  In intraventricular therapy, close the drain for an hour after the first dose.  The trough should equal ten times the MIC of the antibiotic to sterilize the CSF. 

8.  External lumbar catheter infection rates have been reported between .8 and 5 percent.  After LP infection rate is one in 50,000 with 80 cases per year in US. 

9.  Acinteobacter is more common in nosocomial infections that may be resistant.  Initially may use iv meropenem, with or without intrathecal or intraventricular aminoglycoside, if resistant use colistin or polymyxin B.  Colistin in one study sterilized 13/14 patients and cured those.  In another study, all patients treated with colistin survived.