Infections of the CNS (Bacterial, fungal, spirochetal, parasitic) and Sarcoidosis Flashcards
1
Q
ways by which infections reach intracranial structures
A
hematogenous or by extension from cranial structures adjacent to the brain
2
Q
Most common pathogenic organisms in adult
A
pneumococcus (Strep penumo) meningococcus (Neisseria meningitides) haemophilus influenza
3
Q
Most common pathogenic organisms in neonate
A
E. coli Group B strep
4
Q
Most common pathogenic organisms in infants and unvaccinated child
A
H. influenzae
5
Q
organism after neurosurgery or insertion of a cranial appliance
A
staphylococcal
6
Q
Most common bacteria acocunting for 75% of cases
A
H. influenzae N. meningitidis S. penumoniae 4th most common L. monocytogenes
7
Q
implicated organisms after lumbar puncture, spinal anesthesia, shunting procs
A
Pseudomonas Enterobacteriaceae - Klebsiella, Proteus
8
Q
Pneumococcal meningitis is usually suspected in
A
alcoholics
splenectomized patients
very elderly
recurrent Bact Men
Dermal sinus tracts
sickle cell anemia
basilar skull fracture
9
Q
seizures are most often encountered in
A
H. influenza meningitis
10
Q
Most significant factor in the pathogenesis of meningitis in newborns
A
maternal infection UTI, puerperal fever
11
Q
T/F Children in whom meningitis is complicated by subdural effusions are no more likely to have residual neurologic signs and seizures than are those without effusions
A
True
12
Q
T/F Bacteremia is a contraindication to lumbar puncture.
A
False
13
Q
criteria that classifies patient at high risk of bact men
A
positive CSF gram stain CSF absolute neutrophil count at least 1000cells/mL CSf protein at least 80mg/dL. peripheral absolute neutrophil count of at least 10,000 cells/mL history of seizure or after the time of presentation
14
Q
T/F In children, fever subsided more rapidly and the incidence of sensorineural deafness and other nemologic sequelae was reduced, particularly in those children with H. influenzae meningitis
A
True dexamethasonegiven as 0.15mg/kg qid for 4 days
15
Q
prophylaxis for household members of patients with meningococcal meningitis
A
ciprofloxacin single dose rifampin 600mg q12 in adults and 10mg/kg q12 in children for 2 days
16
Q
Osler Triad
A
pneumococcal meningitis
pneumonia
endocarditis
17
Q
Deafness in meningitis is due to
A
suppurative cochlear destruction or aminoglycoside ototoxicity
18
Q
Usually affects immunocompromised individuals and takes the form of brainstem encephalitis treatment
A
Listeria monocytogenes tx: ampicillin 2g IV q4 + gentamicin 5mg per kg IV in 3 divided doses
19
Q
conditions with low CSF glucose
A
sarcoidosis of CNS fungal or TB Meningitis some cases of SAH meningeal carcinomatosis chemically induced inflammation from craniopharyngioma or teratoma meningeal gliomatosis
20
Q
blood cultures are positive in ___% of cases with H.influenzae, meningococcal and pneumococcal meningitis
A
40-60%
21
Q
two ways of differentiating CSF rhinorrhea from nasal secretions
A
nasal secretions have low glucose, CSffrhinorrhea approximates the one obtained via LP protein content high protein - which makes handkerchief stiff - nasal
22
Q
Most specific and sensitive test for CSF otorrhea and rhinorrhea
A
finding of Beta2-transferrin (tau)
23
Q
Recurrent oropharyngeal ulceration, uveitis, orchitis, meningitis
A
Behcet disease
24
Q
recurrent episodes of fever and headache in addition to signs of meningeal irritation
A
Mollaret meningitis
25
recurrent meningitis associated with iridocyclitis and depigmentation of the hair and skin
Vogt-Koyanagi-Harada syndrome
26
Empiric Therapy for Bact Men 0-4 wk
cefotaxime plus ampicillin
27
Empiric therapy for Bact Men 4-12 wk
3rd gen cephalosphorin plus ampicillin plus dexa
28
Empiric Therapy for Bact Men 3mo - 18y
3rd gen cephalopshorin plus vancomycin (+/-ampicillin)
29
Empiric Therapy for Bact Men 18-50 y
3rd gen cephalopshorin plus vancomycin (+/- ampicillin)
30
Empiric Therapy for Bact Men Immunocompromised state
Vanco plus ampicillin and ceftazidime
Intravenous drug abusers have high rates of meningitis due to S. aureus and should receive cefepime or ceftazidime with vancomycin
31
Empiric Therapy for Bact Men Basilar skull fracture
3rd gen cephalosphorin + vanco
32
Empiric Therapy for Bact Men head trauma, neurosurgery CSF shunt
Vanco plus ceftazidime
33
If pseudomonas is considered after neurosurgery
antipseudomonal ceftazidime or cefapim may be revised once with sensitivity of organisms
34
Duration of therapy for most cases of Bact Meningitis
10-14 days
35
T/F The CSF glucose may remain low for many days after other signs of infection have subsided and should occasion concern only if bacteria are present in the fluid and the patient remains febrile and ill,
True
36
Recommended doses for Bact Men with normal renal and hepatic function amikacin ampicillin cefepime ceftazidime ceftriaxone meropenem oxacillin Pen G Vancomycin
Total daily dose/ dosing interval Amikacin 15mg/kg / 8 ampicillin 12 g / 4 cefepime 4-6g / 8 -12 ceftaz 6g / 8 ceftri 4g / 12-24 merop 3-6g / 8 oxacillin 9-12g / 4 pen G 24 million units / 4 vanco 2-4g / 6-12
37
The essential lesion in __________ consists of focal collections of epithelioid cells surrounded by a rim of lymphocytes; frequently there are giant cells, but caseation is lacking
sarcoidosis
38
Syphilis is caused by
Treponema pallidum
39
The treponeme usually invades the CNS within \_\_\_to \_\_\_\_months of inoculation with the organism
3 to 18
40
Neurosyphilis If the nervous system is not involved by the end of the second year, as shown by completely negative CSF, there is _________ chance that the patient will develop neurosyphilis as a result of the original infection; if the CSF is negative at the end of 5 years, the likelihood of developing neurosyphilis falls to ___ percent.
1 in 20 or 5percent after 2nd year 1 percent after 5 years
41
The initial event in the neurosyphilitic infection is ________ , which occurs in approximately ____ percent of all cases of syphilis.
meningitis 25%
42
True or False
All forms of neurosyphilis begin as meningitis and meningeal inflammation are the invariable accompaniment of all forms of neurosyphilis
True
43
The early clinical syndromes are _____________ and \_\_\_\_\_\_\_\_\_\_\_; the late (secondary) ones are ___________ syphilis (1 to 12 years), followed even later by tertiary syphilis, general paresis, __________ , optic atrophy, or subacute myelitis.
aseptic meningitis and meningovascular syphilis
vascular
tabes dorsalis
44
True or False
Because asymptomatic neurosyphilis can be recognized only by the changes in the CSF, it is advisable that all patients with syphilis should have a spinal fluid examination.
True
45
The CSF has been a sensitive indicator of the presence of active neurosyphilitic infection. Enumerate CSF abnormalities
The CSF abnormalities consist of
(1) a pleocytosis of up to 100 cells/mm3, sometimes higher, mostly lymphocytes and a few plasma cells and other mononuclear cells (the counts may be lower in patients with AIDS and those with leukopenia);
(2) elevation of the total protein, from 40 to 200 mg/dL
(3) an increase in gamma globulin (IgG), usually with oligoclonal banding; and
(4) positive serologic tests.
46
True or False In neurosyphilis, The positive serologic tests are the last to revert to normal.
True
47
Most common form of neurosyphilis
Meningovascular syphilis common occurrence after 6-7 years but may occur as early as 9 months up to 10-12 yrs main manifestation of secondary syphilis
48
pathologic changes in meningovascular syphils
The pathologic changes in this disorder consist not only of meningeal infiltrates but also of inflammation and fibrosis of small arteries (Heubner arteritis), which lead to narrowing and, finally, occlusion
49
duration prior to occurrence of paretic neurosyphilis (general paresis, dementia paralytica)
15 to 20 yrs from original infection middle years (35 to 50) are the usual time of onset of paretic symptoms
50
clinical picture in the fully developed form of paretic neurosyphilis
progressive dementia, dysarthria, myoclonic jerks, action tremor, seizures, hyperreflexia, Babinski, Argyll Robertson pupils
51
Pathologic changes in Paretic Neurosyphilis
meningeal thickening
brain atrophy
ventricular enlargement granular ependymitis
special stains: spirochetes are visible in the cortex changes are more pronounced in the frontal and temporal lobes
ependymal surfaces of the ventricles are studded with granular elevations protruding between ependymal cells (granular ependymitis)
52
chief signs in Tabes Dorsalis
absent reflexes at knee and ankle
impaired vibratory and position sense
Romberg sign
major symptoms lightning pains ataxia urinary incontinence
53
T/F There is some ptosis and some degree of ophthalmoplegia in Tabes Dorsalis
True
54
Pathologic findings in Tabes Dorsalis
striking thinness and grayness of posterior roots, principally, lumbosacral
thinning of spinal cord
peripheral nerves E/N
55
T/F In Tabes Dorsalis, if the CSF is positive the patient should be treated with penicillin
True
56
T/F Tabes Dorsalis If there is no pleocytosis, the CSF protein content is normal,and there is no evidence of cardiovascular or other typesof syphilis, antisyphilitic treatment is STILL necessary.
False
57
Prognosis in Syphilitic Optic Atrophy
The prognosis is poor if vision in both eyes is greatly reduced. If only one eye is badly affected, sight in the other eye can usually be saved. In exceptional cases, visual impairment may progress, even after the CSF becomes negative.
58
Pathologic Changes in Syphilitic Optic Atrophy
perioptic meningitis with subpial gliosis and fibrosis replacing degenerated optic nerve fibers vascular lesions with infarction of central parts of the nerve
59
other types of Spinal Syphilis other than Tabes
Syphilitic Meningomyelitis (Erb spastic paraplegia)
Spinal meningovascular syphilis (form of anterior spinal artery syndrome) Syphilitic amyotrophy
Syphilitic amyotrophy with spastic-ataxic paraparesis
60
Treatment of Neurosyphilis
Pen G given IV 18-24 million units daily (3-4 million units q4) for 10-14 days alternative procaine penicillin probenecid ceftriaxone
61
Followup for neurosyphilis
reexamined every 3 - 6 months after tc CSF should retested after 6-mo interval If after 6 months, free of symptoms and CSF abnormalities have been reversed, no further treatment clinical exam at 12mo and another lumbar puncture If pleocytosis remains, another procedure should be repeated after 6 months At the end of 6 months, if there are still an increased number of cells and elevated protein, another full course of penicillin should be given
62
True/False Neurosyphilis A persistent weakly positive serologic (VDRL) test after the cells and protein levels have returned to normal is an indication for additional treatment
False
63
causative spirochete in Lyme Disease
Borrelia burgdorferi
64
Bannwarth syndrome
painful lymphocytic meningoradiculitis
65
striking feature of nearly all types of subacute and chronic infection of the meninges but most notably of tuberculous and syphilitic meningitis
Heubener arteritis subintimal fibrosis
66
The isolation of ______________ from the CSF should suggest the possibility of a brain abscess with an associated meningitis
anaerobic streptococci, Bacteroides, Actinomyces, or a mixture of organisms
67
True or False H. influenza meningitis usually follows upper respiratory and ear infections.
Trure
68
Meningitis in the presence of furunculosis or following a neurosurgical procedure directs attention to the possibility of a \_\_\_\_\_\_\_\_\_\_\_\_\_\_
coagulase-positive staphylococcal infection
69
Ventricular shunts or drains inserted for the relief of hydrocephalus are particularly prone to infection with
coagulase-negative staphylococci and Propionibacterium acnes and diphteroids
70
conditions with substantial red cells in CSF
anthrax meningitis viral infections: Hantavirus, dengue virus, ebola virus some cases of amebic meningoencephalitis
71
bacteria reach the cochlea via the \_\_\_\_\_\_\_\_\_\_, which connects the subarachnoid space to the scala tympani
cochlear aqueduct
72
causative organism in Catscratch fever
Bartonella henselae
gram-negative bacillus
formerly Rochalimaea henselae
73
treatment for Catscratch Fever
firts line azithromycin or doxycycline
rifampicin in recalcitrant cases
74
causative organism in Whipple Disease
Tropheryma whipplei
75
diagnosis in Whipple Disease
PAS staining of an intestinal (jejunal) biopsy
supplemented by PCR testing of teh bowel tissue or biopsy material from brain or lymph node
76
treatment in Whipple Disease
course of induction by penicillin or ceftriaone for 2 weeks followed by TMP-SMX or doxycylcine continued for 1 year
77
treatment in subdural empyema
3rd gen cephalosphorin and metronidazole
78
accounts for the largest number of brain abscess in the modern era
purulent pulmonary infections and bacterial endocarditis
79
imaging findings in brain abscess
T1 - capsule nehances and the interior of abscess is hypotintense
T2 - surrounding edema is apparent, capsule is hypointense,
varaible diffusion reaction within the lesion
abscess capsule tends to be thinner on the side directed to the lateral ventricle
80
single most effective anti-Koch's
isoniazid
adults 5mg/kg
children 10mg/kg
should be given with pyridoxine 50 mg daily
most common SE: neuropathy, hepatitis
81
treatment for TB Meningitis
Isoniazid 5mg/kg/day adults; 10mg/kg in children
Rifampicin 10mg/kg/d in adults; 15mg/kg in children
Ethambutol 15mg/kg/d
Pyrazinamide 20-35mg/kg
Ethionamide (added for resistant cases) 15-25 mg/kg
82
True or False
The essential lesion in sarcoidosis consists of focal collections of epithelioid cells surrounded by a rim of lymphocytes; frequently there are giant cells and there is caseation.
False
caseation is lacking
83
Main therapy for neurosarcoidosis
Corticosteroids
84
most common time of occurrence of meningovascular syphilis is
6-7 years after the original infection
early as 9 months or as late as 12 years
Termed secondary syphilis
85
Most common pathogenic organisms in unvaccinated children
Listeria monocytogenes
staphylococcus
86
Most common pathogenic organism in an infant and unvaccinated child
H. influenzae
87
From the earliest stages of meningitis, changes are also found in the small and medium-sized subarachnoid arteries. The endothelial cells swell, multiply, and crowd into the lumen.
This reaction appears within _____ to ____ hrs
48 to 72 hrs and increases in the days that follow
88
T/F
Bacterial Meningitis
The unusual prominence of the vascular changes may be related to their anatomic peculiarities. Thrombosis in infectious vasculitis is more frequently seen in the arteries.
False
p698
The adventitia of the subarachnoid vessels, both of arterioles and venules, is actually formed by an investment of the arachnoid membrane, which is invariably involved by the infectious process. Thus, in a sense, the **outer vessel wall is affected from the beginning** by the inflammatory process-an **infectious vasculitis.**
**The much more frequentoccurrence of thrombosis in veins than in arteries is probably accounted for by the thinner walls and the slower current of blood flow in the former.**
89
When macrophages are exposed to endotoxins, they synthesize and released cytokines, among which are
Interleukin-1
Tumor necrosis factor
90
Bacterial meningtis
the presence of _____ was the only independent predictor of later seizures
persistent neurologic deficit
91
\_\_\_\_\_\_\_\_\_\_\_\_\_\_ meningitis should be suspected when the evolution is extremely rapid (delirium and stupor may supervene in a matter of hours), when the onset is attended by a petechial or purpuric rash or by large ecchymoses and lividity of the skin of the lower parts of the body, when there is circulatory shock, and especially during local outbreaks of meningitis.
Meningococcal
92
T/F
Meningococcal meningitis
Because a petechial rash accompanies approximately 50 percent of meningococcal infections, its presence dictates immediate institution of antibiotic therapy, even though a similar rash may be observed with certain viral (echovirus serotype 9 and some other enteroviruses), as well as S. aureus infections, and, rarely, with other bacterial meningitides.
True
p700
93
\_\_\_\_\_\_ meningitis is ususally preceded by an infection in the lungs, ears, sinuses or heart valves.
Pneumococcal
94
\_\_\_\_\_\_\_ meningitis usually follows upper respiratory and ear infections in uninoculated child.
H. influenzae meningitis
95
Cultures of the spinal fluid, which prove to be positive ______ percent of cases of bacterial meningitis
70 to 90 %
96
Cranial nerve abnormalities are particularly frequent in ______ meningitis
pneumococcal
97
begins as unilateral or cervicla adenopathy occurring after a seemingly innocuous scratch from an infected cat
high fever, encephalopathy, seizures, status epilepticus
Catscratch Fever
98
pathogenesis of menigitis
the infection in both mother and infant is most often caused by
gram negative enterobacterua - E. coli
Group B strep
less often pseudomonas, listerua, S. aureus or epidermidis,
group A strep
99
middle-aged woman
fever, weight loss, anemia, steatorrhea, abdominal pain, distention, athralgia, lymphadenopathy, hyperpigmentation
neuro: slowly progressive memory loss/dementia, supranuclear opthalmoplegia, ataxia, seizures, myoclonus, nystagmus, highly characteristic oculomasticatory movement described as myorhythmia
diagnosis: PAS-staining of jejunal biopsy
Whipple Disease
100
source of infection cannot be ascertained in how many percent of brain abscess cases
20%
101
T/F Brain Abscess
## Footnote
Endocarditis from the implantation in the brain of streptococci of low virulence (alpha and gamma streptococci) or similar organisms on valves previously damaged by rheumatic fever seldom gives rise to a brain abscess.
True
p714
In contrast, organisms such as S. aureus and gram-negative bacteria have a propensity to cause abscesse
102
How many percent of patients with congenital heart disease are complicated by brain abscess?
5%
p715
103
T/F
The capsule of an abscess is uniform in thickness.
False
NOT uniform in thickness, frequently being thinner on its medial (paraventricular) aspect
-earlier restrricted diffusion on MRI
104
Brain Abscess
type of organisms tends to vary with source
accidental or surgical trauma
drug addicts who inject themselves
endocarditis
otitic infections
lung and paransal sinuses
accidental or surgical trauma - staphylococcal
drug addicts who inject themselves - staphylococcal
endocarditis - staphylococcla
otitic infections - enteric
lung and paransal sinuses - anaerobic streptococci
105
Cryptococcous is a common soil fungus found in
roosting sites of brids, especially pigeons
106
portal of entry for cryptococcus
respiratory,
less often skin and mucous membranes
107
T/F
Crypto CFS studies
The gluose is reduced in 3/4 of cases and may reach high levels.
Treu
p732
108
rate of positive tests for India ink CSF
75%
p732
109
CALAS - if negative, excludes cryptococcal meningitis in \_\_\_\_
90% reliability in AIDS patients and slightly less in others
p732
110
culture medium crypto
Saboraud's agar
111
Treatment for Crypto Men in pts without AIDS
Amphotericin B 0.7-1.0mg/kg/d
addition of Flucytosine 100mg/kg/d results in fewer failures or relapses, more rapid sterilization of CSF ad less nephrotoxicity, permits reduction of Ampro dose 0.3-0.5mg/kg/f
success rate 75-85% in immunocompetentq
112
frequent complication for Ampho B
renal tubular acidosis
113
Toxoplasmosis which is caused by Toxoplasma gondii is an obligate intracellular parasite readily recognized in \_\_\_\_
Wright- or Giemsa-stained preparations
114
treatment for toxoplasmosis
Oral sulfadiazine 4g initially then 4-6 g daily and pyrimethamine 200mg intitialy then 50-100mg daily
leucovorin 15-20 mg daily to countreact antifolate effect of pyrimethamine
treatment for 6 weeks
115
fatal disease characterized by headache, seizures, coma, with diffuse cerebral edema, and only rarely, focal features such as aphasia, hemiplegia, ataxia, hemianopia
retinopathy of macular whitening, orang or white discoloration of vessel, intraretinal blot type hemorrhages
neurologic symptoms appear 2nd-3rd week
Malaria
116
treatment for Malaria
quinine
artesunate
once coma and convulsions supervene, 20-30% mortality
117
* begins with a chancre at the site of inoculation
* localized lymphadenopathy, posterior cervical
* parasitemia
* 2nd year of infection: meningoencephalitis
* chronic progressive syndrome consisting of reversal or disruption of circadian rhythm, vacant facial expression, ptosis, ophthalmoplegia, dysarthria, muteness, seizures, apathy, stupor, coma
Trypanosomiasis
Tx: melarsoprol
118
* infection from ingestion of uncooked infected pork
* early symptoms: gastroenteritis
* end of 1st week up to 4-6 weeks: fever, pain and tenderness of muscles, edema of conjunctivae, eyelids, fatigue
* headache, stiff neck, mild confusional state, delirium, coma, hemiplegia, aphasia
* heart is often involved
* seldom fatal
Trichinosis, Trichinellosis
tx: albendazole and steroids
119
* infection with pork tapeworm *Taenia solium*
* most often presents with seizures, although many are asymptomatic
* only when the cyst degenerates many months or years after that an inflammatory and granunlomatous reaction is elicited
* some, large subarachnoid or intraventricular cysts may obstruct CSF flow
* tx: albendazole
Cysticercosis
120
which of the ffg organisms has the tendency to localize to the ffg:
a. cerebral hemisphere
b. spinal cord
schistosoma hematobium, mansoni
a. cerebral hemisphere - japonicum
b. spinal cord - mansoni
121
T/F
lesions of Schistosoma in the brain calcify
False
lesions DO NOT cakcify
p739
122
* seen in travelers who have bathed in lakes or rivers where the snail hosts of the parasite are plentiful
* initial manifestation: local skin irritation at teh site of entry of the parasite (swimmer's itch)
* large serpiginous urticarial rash on the trunk
* katayama fever
* headaches, convulsions, papilledema, simulates brain tumor
Schistosomiasis
123
Schistosoma infections mainly mansoni tend to localize in the spinal cord causing an acute or subacute myelitis that is concentrated in
conus medullaris
124
tx for schistosomiasis
praziquantel 20mg/kg tid
125
clinical features of nervous system involvement
biosy evidence of granulomas in other tissues: lymph nodes, lung, bones, uvea, skin, muscle
imaging: meningeal involvement, periventricular and white matter lesions, nodular or streak-like perivenular enhancement
Neurosarcoidosis
126
Most certain indication for steroid therapy in neurosarcoidosis
recent onset of neurologic symptoms indicating an active phase
or a disabling syndrome such as myelopathy
127
