Sunday, February 24, 2013

Pearls on carotid cavernous fistulas

from Wijdicks text on acute neurology

1.  Associations--
      remote trauma
      post transsphenoidal surgery
      post ethmoidal surgery
     post carotid surgery
     Ehlers Danlos syndrome

2.  Visual loss is due to increased intraocular pressure or reverse of flow or thrombus in superior opthalmic vein (SOV).  Balloon or coil occlusion has been reported (sometimes) to reverse blindness

3.  On angiography, immediate opacification of carotid sinus is seen after carotid injection.

4.Clinical findings include III n palsy, lid swelling, tortuous veins, dis edema and visual loss.

tests to consider in patients with encephalitis

serology- HIV, EBV, acute and convalescent phases St Louis encephalitis, eastern equine encephalitis, LaCrosse and West Nile viruses; acute and convalescent phase serum titers of myc. pneum, ricketsii ricketsiae, ehrlichia chaffensis, anaplasma phagocytophilum; rpr and fta;  lyme (ELISA and Western blot), IgG for toxoplasma; serum cryptococcal antigen; complement fixing or immunodiffusion antibodies for coccidio species

blood cultures;

Respiratory secretions pcr for myc. pneum;

CSF cultures;  IgM for St Louis, West Nile and VZV; vdrl and fta, IgG index, lyme (elisa and Western blot), CSF cryptococcal antigen; CSF histoplasma antigen;  complement fixing or immunodiffusion antibodies for coccidio species

CSF pcr's for HSVE I and II, enteroviruses, VZV, EBV, ehrlichia and anaplasma species, myco. pneum.

blood smears for morulae

culture respiratory secretions,nasopharyx, throat and stool

skin culture of rash if present for HSV and VZV

urine -- histoplasma antigen

Signs indicating causes in confused febrile patients

from  Wijdicks, The practice of emergency and critical care neurology.

Rash-- ricketsiae, aspergillus, vasculitis

petechiae-- TTP, meningococcemia, endocarditis, drug eruption, leukemia

splenomegaly-- toxo, TB, sepsis, HIV, lymphoma

pulmonary infiltrates-- legionella, fungi, TB, mycoplasma, pneumonia, tick borne, Q fever

Saturday, February 16, 2013

Meningococcal meningitis and corticosteroids

Brust JCM.  Meningococcal meningitis, dexamethasone and Class III evidence(editorial) Neurology 2012; 79: 1528-9.

The most recent Cochran review shows a benefit of adjunctive dexamthasone to mortality in Streptococcalbut not N meningitidis meningitis with benefits to adults and children in high but not low income countries ( See Brouwer MC et al, 2010).  Significantly, however, dexamethasone does no harm.  Recommendation is .6 mg/ for four days.  It should be given prior to or with the first dose of antibiotic before lysis occurs.  In practice, steroids rarely are stopped when Neiss men is identified as the organism, but that does not harm the patient.