3. CASE 1 History
14-year-old girl, 10-day history of
progressive weakness
3 weeks before, rhinorrhea,
cough, malaise
8 days after, lower-extremity
weakness and difficulty walking
Diffuse muscle pain and
progressive weakness that
extended to upper extremities
3 days before this, developed a hoarse voice and SOB
Difficulty urinating and decreased oral intake
No fever, cough, vomiting, diarrhea
4. EXAMINATION
Afebrile, ill-appearing
Heart rate:
118 bpm
Respiratory rate:
28 breaths/min
Blood pressure:
168/122 mm Hg
Oxygen saturation:
93% at room air
Lungs auscultation:
diffuse, poor aeration
Heart sounds:
normal, no murmur
5. NEUROLOGIAL EXAM.
Muscle strength symmetric but diminished
Lower extremities: 2/5, upper extremities: 4/5
Sensation intact to light touch, loss of vibratory
sense
Lower extremities: No DTR,
upper extremities: diminished (1+),
absent plantar reflexes
Cranial nerves II-XII intact; weak cough and gag
reflex, impaired handling of secretions.
The remainder of her examination is
unremarkable.
7. INVESTIGATIONS
CBC and a basic metabolic panel:
within normal limits
LP: opening pressure of 15 cm H20
CSF analysis:
2 WBC/HPF
4 RBC/HPF
No organisms
Protein 96 mg/dL (960 mg/L)
Glucose 72 mg/dL (3.99 mmol/L)
MRI brain and spine
Transported to the ICU, Intubated
16. Two types of reactions are seen in peripheral nerve injury
Injury of the neuron and its axon leads
to axonal degeneration,
a. neurone cell body (neuropathy)
b.or its axon (axonopathy)
•Dysfunction of the
Schwann cell or damage to
myelin sheath leads to a
loss of myelin lead to
(segmental demyelination).
21. VARIANTS
Miller Fisher syndrome (MFS)
Acute motor axonal neuropathy (AMAN)
Acute motor sensory axonal neuropathy
(AMSAN)
Acute panautonomic neuropathy
Bickerstaff’s brainstem encephalitis (BBE),
22. Miller Fisher syndrome (MFS)
Classic triad of ophthalmoplegia, ataxia,
and areflexia
Diplopia usually initial symptom, followed
by limb or gait ataxia
Descending paralysis
Elevated antibodies to GQ1b
26. Prognosis
Nadir of clinical deficits at 4 weeks
5-20% have fulminant course
Residual deficit
Recovery at 1 year follow-up:
62% had recovered completely,
14% could walk but not run,
9% could not walk without assistance,
4% remained bed bound or ventilated,
8% died
31. Anterior Horn Cell
Type 1 (Werdning- Hoffman
disease)
• Clinically apparent at birth
• Tongue fasciculations,
floppiness, absent tendon
reflexes and gen. muscle
atrophy,
• Recurrent chest infections
and death before the age
of 2 yrs. due to resp.
failure.
Spinal Muscular
Atrophy
40. CASE 2
Six-year-old girl, unable to walk without
assistance for few hours
Tingling sensation in her finger toes
yesterday
Six hours later stagger and fall
Next day unable to walk
41. PHYSICAL EXAMINATION
Alert, afebrile
Truncal instability, wide-based, ataxic gait
Neurological examination:
Muscle strength in the legs and arms 4/5
Dysmetria on finger-to-nose testing
DTR diminished at the left knee, normal
elsewhere
Sensations and cranial nerves normal, as was
the rectal-sphincter tone
42. INVESTIGATIONS
Chest x-ray
Routine laboratory studies
Tests for toxic substances
Stool culture
MRI head and neck no abnormalities
CSF analysis:
Protein 29 mg/dl
Glucose 71 mg/dl (3.9 mmol per liter)
Lymphocyte count of 2 per cubic millimeter.
Gram's staining and culture negative
Nerve-conduction studies
43.
44. COURSE IN HOSPITAL
48 hours later lethargic and irritable
Symmetric leg weakness increased, with muscle
strength of 3/5.
DTR at the knees and ankles were absent
Due to ascending paralysis and hypoventilation,
transferred to the ICU for intubation
By 72 hours, motor strength 2/5
Listlessness, slurred speech, and bilateral ptosis
68. b
w
N
S
Generalized Seizures
Encephalopathic Coma with or
without Seizures
All disorders that cause
hypoglycemia
Maple syrup urine disease
Most hepatic glycogen storage
diseases
Nonketotic hyperglycinemia
Galactosemia, hereditary fructose
intolerance
Diseases producing extreme
hyperammonemia
Fructose-1,6-bisphosphatase
deficiency
Disorders of the urea cycle
Disorders of the propionate pathway Disorders of the propionate pathway
HMG-lyase deficiency Disorders of beta oxidation
Disorders of beta oxidation Congenital lactic acidosis (PCD)
Pyruvate carboxylase deficiency
(PCD)
Maple syrup urine disease
69. Blood and Plasma Urine
Arterial blood gas Glucose
Electrolytes-anion gap pH
Glucose Ketones
Ammonia Reducing
substances
Liver enzymes Organic acids
Complete blood count,
differential,†
and platelet
count
Acylcarnitine
Orotic acid
Lactate, pyruvate
Organic acids
Amino acids
Carnitine
70. Disease Affected Enzyme
Organs
Affected Clinical Syndrome
Neonatal
Manifestations
Type I: von Gierke Glucose-6-
phosphatase
Liver, kidney,
GI tract,
platelets
Hypoglycemia, lactic acidosis, ketosis,
hepatomegaly, hypotonia, slow
growth, diarrhea, bleeding
disorder, gout,
hypertriglyceridemia, xanthomas
Hypoglycemia, lactic
acidemia, liver may
not be enlarged
Type II: Pompe Lysosomal α-
glucosidase
All, notably
striated
muscle,
nerve
cells
Symmetric profound muscle
weakness, cardiomegaly, heart
failure, shortened P-R interval
May have muscle
akness,
cardiomegaly, or
both
Type III: Forbes Debranching enzyme Liver,
muscles
Early in course hypoglycemia,
ketonuria, hepatomegaly that
resolves with age; may show
muscle fatigue
Usually none
Type IV: Andersen Branching enzyme Liver, other
tissues
Hepatic cirrhosis beginning at several
months of age; early liver failure
Usually none
Type V: McArdle Muscle
phosphorylase
Muscle Muscle fatigue beginning in
adolescence
None
Type VI: Hers Liver phosphorylase Liver Mild hypoglycemia with
hepatomegaly, ketonuria
Usually none
Type VII: Tarui Muscle
phosphofructok
inase
Muscle Clinical findings similar to type V None
Type VIII Phosphorylase kinase Liver Clinical findings similar to type III,
without myopathy
None
Notas do Editor
Normal CSF findings
Electrophysiology
Grades of DTR 0 1 2n 3 4c
Albuminocytologic dissociation elevation of CSF protein with normal CSF cell count).
Indication to do LP
lack of CSF pleocytosis
H1N1 and GBS
Infection
Treatment
Vaccine
A 14-year-old boy presents to the emergency department (ED) with a 10-day history of progressive weakness. The patient reports experiencing rhinorrhea, cough, and malaise approximately 3 weeks before admission. He developed lower-extremity weakness and difficulty walking 8 days after the onset of the upper respiratory tract infection symptoms. He was evaluated at a local hospital, where he was diagnosed with dehydration, treated with intravenous fluids, and discharged to home. Despite these measures, his lower-extremity weakness did not improve. Over the following 7 days, he began experiencing diffuse muscle pain and progressive weakness that extended to his upper extremities. During the 3 days before this presentation, he developed a hoarse voice and shortness of breath. He also notes that he is now having difficulty urinating and has decreased oral intake. He currently denies having any fever, cough, vomiting, or diarrhea. The patient's past medical history is significant only for attention deficit hyperactivity disorder (ADHD), for which he takes methylphenidate. He has had no previous hospitalizations, has no known drug allergies, and has had all recommended childhood immunizations. His family history is noncontributory.
The physical examination reveals an afebrile, ill-appearing teenager, with a heart rate of 118 bpm, a respiratory rate of 28 breaths/min, a blood pressure of 168/122 mm Hg, and an oxygen saturation of 93% while breathing room air. Auscultation of the lungs reveals diffuse, poor aeration. His heart sounds are normal, without any appreciable murmur. His strength is symmetric but diminished to 2/5 in his lower extremities and 4/5 in his upper extremities (5/5 being normal strength). The patient's sensation is intact to light touch, but there is a loss of vibratory sense. He has no deep tendon reflexes in his lower extremities, diminished deep tendon reflexes (1+) in his upper extremities, and absent plantar reflexes. Cranial nerves II-XII are intact; however, he has a weak cough and gag reflex, with impaired handling of secretions. The remainder of his examination is unremarkable.
The patient is intubated for progressive respiratory distress and loss of airway-protective reflexes. He is fluid-resuscitated with a liter of intravenous normal saline. An electrocardiogram (ECG) is obtained, which demonstrates sinus tachycardia. The initial laboratory analysis, including a complete blood cell (CBC) count and a basic metabolic panel, is within normal limits. A lumbar puncture is performed, with an opening pressure of 15 cm H20. The cell count and Gram stain of the cerebrospinal fluid (CSF) demonstrates 2 white blood cells per high power field, 4 red blood cells per high power field, and no organisms. Additional analysis of the CSF shows a protein concentration of 96 mg/dL (960 mg/L) and glucose concentration of 72 mg/dL (3.99 mmol/L). The patient is sent for magnetic resonance imaging (MRI) of his brain and spine (see Figure 1) and is transported to the pediatric intensive care unit (ICU) for further management.
The lumbrosacral MRIs (see Figures 1 and 2) demonstrate nerve root enhancement of the cauda equina on axial post-contrast T1-weighted sequences.
GBS is also known as acute inflammatory demyelinating polyneuropathy, acute idiopathic polyradiculoneuritis, acute idiopathic polyneuritis, French Polio, Landry's ascending paralysis and Landry Guillain Barre syndrome.
1859
André Strohl
Two soldiers in Amiens developing paralysis and loss of DTRs.
A new diagnostic feature: albuminocytologic dissociation in the CSF
No mention of Landry
Mil nofsa sis
Demyelinating and axonal forms of GBS have both been described. In the demyelinating form, segmental demyelination of peripheral nerves is found in association with infiltration of inflammatory cells. GBS with axonal degeneration may occur without demyelination or inflammation.
Many authors believe that the mechanism of disease involves an abnormal T-cell response precipitated by a preceding infection. Some of the pathogenic triggers of GBS include Epstein-Barr virus, cytomegalovirus, hepatitis, varicella, Mycoplasma pneumonia, and Campylobacter jejuni, perhaps most common. These pathogens are believed to activate CD4+ helper-inducer T cells, which are particularly important mediators of disease. A variety of specific endogenous antigens including myelin P-2, ganglioside GQ1b, GM1, and GT1a may be involved in this response. Molecular mimicry of the triggering pathogens resembling antigens on peripheral nerves leads to an overzealous and autoimmune response mounted by T-cell lymphocytes and macrophages.
GBS is an autoimmune-mediated disease with environmental triggers (eg, pathogenic or stressful exposures).
Several infections (eg, Epstein-Barr virus, cytomegalovirus, hepatitis, varicella, other herpes viruses, Mycoplasma pneumoniae, C jejuni) as well as immunizations have been known to precede or to be associated with the illness. C jejuni seems to be the most commonly described pathogen associated with GBS. Occasionally, surgery has been noted to be a precipitating factor.
Many forms of GBS are demyelinating. However, more recently, an axonal form of GBS has been described after a diarrheal illness secondary to C jejuni.
Other diseases can present with a GBS-like picture.
Frequency
United States
Estimates of annual incidence of GBS range from 0.5-1.5 per 100,000 in individuals younger than 18 years. No clear seasonal preponderance of GBS has been noted in the United States although some seasonal variation is reported in neighboring Mexico.
International
Risk of occurrence is similar throughout the world, in all climates, and among all races, except for reports of seasonal predilections noted in some countries for Campylobacter -related GBS in the summer and upper respiratory illness—related GBS in the winter. Recently, epidemics of an illness closely resembling GBS were noted to occur annually in the rural areas of North China, particularly during the summer months. These epidemics have been associated with C jejuni infection, and many of these patients are found to have antiglycolipid antibodies. Because these cases involve degeneration of peripheral motor axons without much inflammation, the syndrome has been termed acute motor axonal neuropathy (AMAN). Recently, other region-specific demographic studies have shown discrete preponderance of AMAN. For example, in a prospective pediatric study (n=78) from Mexico, AMAN seemed to exhibit a seasonal peak from July-September unlike AIDP, which seemed to be more evenly distributed throughout the year.1
Mortality/Morbidity
Overall mortality rate in childhood GBS is estimated to be less than 5%; mortality rates are higher in medically underserved areas. Deaths are usually caused by respiratory failure, often in association with cardiac arrhythmias and dysautonomia. Full recovery within 3-12 months is experienced by 90-95% of pediatric patients with GBS. Between 5% and 10% of individuals have significant permanent disability.
In general, the outcome of GBS is more favorable in children than in adults. Deaths are relatively rare, especially if recognition of the signs of this disorder are acted upon quickly. The recovery period is longer than the duration of the acute illness, often weeks to months, with a median estimated recovery time of 6-12 months. In one small pediatric series, the median time from onset of symptoms to complete recovery was 73 days.
The most common serious complications are weakness of the respiratory muscles and autonomic instability. Pneumonia, adult respiratory distress syndrome, septicemia, pressure sores, ileus, constipation, gastritis, dysesthesias, and pulmonary embolus are also important potential complications. During the acute progressive phase of the disease, close attention should be paid to respiratory status.
In cooperative children older than 5 years, respiratory function measurements such as vital capacity or maximal inspiratory force (MIF), expressed in units of cc H2 O pressure can be valuable. MIFs are also known as negative inspiratory force (NIF). MIFs less than -20 cc H2 O pressure can be an indication of poor inspiratory ability and respiratory distress. MIFs are normally greater than -40 cc H2 O pressure, thus the more negative, the better MIF.
MIFs provide objective data to follow and compare. This measure is unfortunately difficult to monitor in young (<5 y) and any uncooperative child. Experienced pediatric respiratory therapists can be very valuable in these measures.
Blood gases and chest radiographs are also valuable in assessing respiratory parameters.
Recurrence of GBS occurs in approximately 5% of cases, sometimes many years after the initial bout. Recurrence is generally thought to be relatively uncommon in children but has been reported in one small series to be observed in nearly 12% of cases in the first 2-3 weeks after intravenous immunoglobulin (IVIG) administration.
Some patients experience a chronic progressive course, known as chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).
Race
Although major histocompatibility locus genes may play a role in susceptibility to GBS, no evidence exists for any racial predilection.
Sex
Males appear to be at greater risk for GBS than females. This increased predilection for GBS has also been reported as a male-to-female ratio of 1.2:1 in a recent review of children with GBS. A similar ratio of 1.26:1 was found in a prospective study of 95 children with GBS in Western Europe.2 In a prospective study of 78 children from Mexico, acute inflammatory demyelinative polyneuropathy (AIDP) was 3 times more common in male patients than in female patients, while acute motor axonal neuropathy (AMAN) was slightly more common in males than in females .1 In Pakistan, a combined adult and pediatric Guillain-Barré study (n=175) reported that 68% of all patients were male.3
Age
Individuals older than 40 years have a steadily increasing risk, peaking at age 70-80 years, compared with younger individuals. Children are at lower risk than adults, with incidence ranging from 0.5-1.5 per 100,000 children.
Recent retrospective reviews of childhood GBS reported the average age to be in the range of 4-8 years. Individuals affected with GBS can be as young as 1 year.
After the first week of symptoms, analysis of the CSF typically reveals normal opening pressures, fewer than 10 white blood cells per high power field (typically mononuclear), and an elevated protein concentration (greater than 45 mg/dL). This finding, also known as albuminocytologic dissociation, may be delayed. As a result, a repeat lumbar puncture may be required as the protein values may not rise for 1-2 weeks, and maximum protein values may not be seen for 4-5 weeks.
In addition, gadolinium-enhanced lumbosacral MRI may demonstrate enhancement of the cauda equina nerve roots. This imaging modality has been described to be 83% sensitive for acute Guillain-Barré syndrome, and abnormalities are present in 95% of typical cases.[3]
Electrophysiologic studies are the most specific and sensitive tests for confirming the diagnosis. Most patients demonstrate slowing of nerve conduction 2-3 weeks after the onset of symptoms. There are a variety of abnormalities seen in Guillain-Barré syndrome that indicate evolving multifocal axonal demyelination in peripheral nerves, spinal roots and/or cranial nerves. Abnormalities seen on electromyography include partial motor conduction block, slowed nerve conduction velocities, abnormal temporal dispersion, and prolonged distal latencies.[4] The earliest finding, which may be present within days of symptom onset, is prolongation or absence of the F responses, which indicates demyelination involving the proximal nerve roots.
GBS with a descending pattern of weakness seen in 14% cases;.
iii. In 1/3 of cases, the degree of weakness in the arms and legs is roughly equal.
About 70% of patients present with loss of reflexes; less than 5% retained all reflexes during the illness;
>50% will present with symmetric distal limb paresthesias
Some discomfort reported in 2/3 of patients
1/2 of GBS patients have some degree of cranial nerve dysfunction during their illness.
due to diaphragmatic weakness occurs in about 1/3 of patients.
occurs in about 65% of cases
The diagnosis of Guillain-Barré syndrome (GBS) is typically made by the presence of a progressive ascending weakness with areflexia. An LP, electrodiagnostic studies, or occasionally MRI findings can give support for this diagnosis. increased protein >45 mg/dL within 3 wk of onset) without evidence of active infection (lack of CSF pleocytosis), as originally noted by Guillain and Barré.
The CSF findings may be normal within the first 48 hours of symptoms, and occasionally the protein may not rise for a week. Serial spinal taps are sometimes often warranted if early studies are normal. Usually by 10 days of symptoms, elevated CSF protein findings will be most prominent.
Most patients have fewer than 10 leukocytes per milliliter, but occasionally a mild elevation (ie, 10-50 cells/mL) is seen. Greater than 50 mononuclear cells/mL of CSF casts some doubt on the diagnosis of GBS.
Spine MRI findings: Nearly 2 weeks after presentation of symptoms, lumbosacral MRI can show enhancement of the cauda equina nerve roots with gadolinium. This imaging study has been described to be 83% sensitive for acute GBS and present in 95% of typical cases.
MRI may demonstrate enhancement of the cauda equina nerve roots. This imaging modality has been described to be 83% sensitive for acute Guillain-Barré syndrome, and abnormalities are present in 95% of typical cases.[3]
Temperature, blood pressure, heart rate, respiratory capacity (eg, MIFs), blood gases (if necessary), and urine output of the patient should be monitored.
Intubation and mechanical ventilation should be considered when vital capacity falls below 15 mL/kg body weight or arterial pressure of oxygen falls below 70 mm Hg (or the patient has significant fatigue). Maximal inspiratory flows (MIFs) or negative inspiratory flows (NIFs) are important measures in older children.
During the acute phase of the illness, orthostatic hypotension and urinary retention also may cause significant problems.
Acute motor axonal neuropathy (AMAN)[16], a.k.a. Chinese Paralytic Syndrome, attacks motor nodes of Ranvier and is prevalent in China and Mexico. It is likely due to an auto-immune response directed against the axoplasm of peripheral nerves. The disease may be seasonal and recovery can be rapid. Anti-GD1a antibodies[17] are present. Anti-GD3 antibodies are found more frequently in AMAN.
Acute motor sensory axonal neuropathy (AMSAN) is similar to AMAN but also affects sensory nerves with severe axonal damage. Like AMAN, it is likely due to an auto-immune response directed against the axoplasm of peripheral nerves. Recovery is slow and often incomplete
Acute panautonomic neuropathy is the most rare variant of GBS, sometimes accompanied by encephalopathy. It is associated with a high mortality rate, due to cardiovascular involvement, and associated dysrhythmias. Impaired sweating, lack of tear formation, photophobia, dryness of nasal and oral mucosa, itching and peeling of skin, nausea, dysphagia, constipation unrelieved by laxatives or alternating with diarrhea occur frequently in this patient group. Initial nonspecific symptoms of lethargy, fatigue, headache, and decreased initiative are followed by autonomic symptoms including orthostatic lightheadedness, blurring of vision, abdominal pain, diarrhea, dryness of eyes, and disturbed micturition. The most common symptoms at onset are related to orthostatic intolerance, as well as gastrointestinal and sudomotor dysfunction (Suarez et al. 1994). Parasympathetic impairment (abdominal pain, vomiting, obstipation, ileus, urinary retention, dilated unreactive pupils, loss of accommodation) may also be observed.
It is characterized by acute onset of ophthalmoplegia, ataxia, disturbance of consciousness, hyperreflexia or Babinski’s sign (Bickerstaff, 1957; Al-Din et al.,1982). The course of the disease can be monophasic or remitting
MRI may demonstrate enhancement of the cauda equina nerve roots. This imaging modality has been described to be 83% sensitive for acute Guillain-Barré syndrome, and abnormalities are present in 95% of typical cases.[3]
Electrophysiologic studies are the most specific and sensitive tests for confirming the diagnosis. Most patients demonstrate slowing of nerve conduction 2-3 weeks after the onset of symptoms. There are a variety of abnormalities seen in Guillain-Barré syndrome that indicate evolving multifocal axonal demyelination in peripheral nerves, spinal roots and/or cranial nerves. Abnormalities seen on electromyography include partial motor conduction block, slowed nerve conduction velocities, abnormal temporal dispersion, and prolonged distal latencies.[4] The earliest finding, which may be present within days of symptom onset, is prolongation or absence of the F responses, which indicates demyelination involving the proximal nerve roots.
Value as a prognostic marker in children is still under evaluation.
Anti-GM1, GM1b, GD1a, and GalNAc-GDIa have been associated in adults with C jejuni infection, acute motor axonal neuropathy, a more severe course, and more residual neurologic deficits.
A recent study of 32 Japanese children diagnosed with Guillain-Barr é syndrome identified one or more of these antibodies in 44% and in 64% of those who met the electrodiagnostic criteria for acute motor axonal neuropathy. Those with positive antibodies had a more prolonged recovery with more residual symptoms at the end of the study.4 However, another study in Western Europe did not find any difference in clinical course or outcome in the 4 patients with positive antibodies out of 63 total children with Guillain-Barr é syndrome.5
Other antibodies are associated with specific forms of Guillain-Barr é, such as GQ1b with Miller-Fisher syndrome and GT1a with pharyngeal-cervical-brachial variant, and these may be useful in the diagnostic workup of variant clinical presentations.
ICU monitoring
ii. Basic medical management often determines mortality and
morbidity.
mechanical ventilation usually required if VC drops below
about 14 ml/kg; ultimate risk depending on age, presence of
accompanying lung disease, aspiration risk, and assessment
of respiratory muscle fatigue
Autonomic dysfunction
i. Autonomic dysfunction may be self-limited; do not over-treat.
ii. Sustained hypertension managed by angiotensin-converting
enzyme inhibitor or beta blocking agent. Use short acting
intravenous medication for labile hypertension requiring
immediate therapy.
iii. Postural hypotension treated with fluid bolus or positioning.
iv. Urinary difficulties may require intermittent catherization.
d. Noscomial infections usually involve pulmonary and urinary tracts.
i. Occasionally central venous catheters become infected.
ii. Antibiotic therapy should be reserved for those patients showing
clinical infection rather than colonization of fluid or sputum
specimens.
PE demonstrated to be beneficial if instituted
within two weeks of illness.
Intravenous immunoglobulin (IVIg)
Intravenous immunoglobulin (IVIg)
1. When compared to PE, IVIg shown to be as efficacious as
PE and with few adverse effects (Sandoglobulin trial).
2. No benefit to combined PE and subsequent IVIg over either
alone.
3. Mechanism of IVIg improvement not completely
understood.
a. neutralization of proinflammatory cytokines
b. down regulation of pathogenic antibodies
c. modulation of Fc receptor-mediated phagocytosis
d. inhibition of complement deposition
e. promotion of remyelination
4. side effects
a. headache most common
b. transient fever, serum sickness reaction, aseptic
meningitis, elevated LFTs and WBCs, acute renal
tubular necrosis, hypercoagulable state with risk
myocardial infarction or stroke
c. anaphylaxis may occur in patients with IgA
deficiency if IgA rich IVIg administered.
d. transmission of hepatitis C reported, but not HIV.
5. relapse rate about 10% which is similar to PE
Majority have progressive illness with nadir of clinical deficits at 4 weeks.
i. 3/4 reach nadir by 1 week.
b. 15% have mild illness, remain ambulatory, and recovery after few weeks.
c. 5-20% have fulminant course, develop flaccid paralysis, ventilator
dependence, and axonal degeneration.
i. Such patients have delayed and incomplete recovery.
d. Residual deficit: about 1/3 of cases require ventilator assistance, 1/2 are
either chair or bed bound, and 7% have trouble walking. The remainder
are ambulatory.
e. Recovery at 1 year follow-up: 62% had recovered completely, 14% could
walk but not run, 9% could not walk without assistance, 4% remained bed
bound or ventilated, 8% died.
f. Poor prognostic features
i. age greater than 60
ii. history of preceding diarrhea illness
iii. recent CMV infection
iv. fulminant and rapidly progressive course
v. ventilator dependence
vi. greatly reduced CMAP amplitudes or inexcitable nerves
g. Mortality about 5-10% with aggressive ICU care.
h. About 3-6% of patients with typical GBS have developed a chronic
relapsing course consistent with CIDP.
i. No distinguishing features.
ii. Most relapses responsive to steroids.
Type 1 (Werdning- Hoffman disease) It is clinically apparent at birth or in the early months of life, characterized by tongue fasciculations, floppiness, absent tendon reflexes and gen. muscle atrophy, recurrent chest infections and death before the age of 2 yrs. due to resp. failure.
performed 24 hours before the maximal weakness revealed that the distal latency of the ulnar nerve was prolonged, at 6.0 msec (normal value, <2.5) and that the amplitude of the muscle action potential of the peroneal nerve was moderately reduced (Table 1). There was no evidence of conduction block or late components.
The diagnostic features of the Guillain–Barré syndrome are a progressive paralysis in both legs, both arms, or all four limbs; areflexia or hyporeflexia; a cerebrospinal fluid protein level that exceeds 40 mg per deciliter (although the protein level may be normal initially), with a mononuclear-cell count of less than 10 per cubic millimeter; and a progression to peak neurologic impairment within four weeks after the onset of symptoms.8 In contrast, tick paralysis is characterized by normal cerebrospinal fluid and by a progression to peak paralysis over a period of hours to a few days.
The clinical differentiation of tick paralysis from the Guillain–Barré syndrome and other causes of ascending paralysis is crucial because the therapies for these conditions differ. Features of four common syndromes of generalized paralysis in previously healthy patients are summarized in Table 2. The diagnostic features of the Guillain–Barré syndrome are a progressive paralysis in both legs, both arms, or all four limbs; areflexia or hyporeflexia; a cerebrospinal fluid protein level that exceeds 40 mg per deciliter (although the protein level may be normal initially), with a mononuclear-cell count of less than 10 per cubic millimeter; and a progression to peak neurologic impairment within four weeks after the onset of symptoms.8 In contrast, tick paralysis is characterized by normal cerebrospinal fluid and by a progression to peak paralysis over a period of hours to a few days. Nerve-conduction studies in patients with tick paralysis may resemble those in patients with the Guillain–Barré syndrome: findings in both conditions include prolonged latency of the distal motor nerves, diminished nerve conduction velocity, and reduction in the amplitudes of muscle and sensory-nerve action potentials, as observed in our patient.
Acute lesions of the spinal cord are distinguished by sensory changes, urinary retention, fecal incontinence, and laxity of anal-sphincter tone.
Poliomyelitis, with which tick paralysis was often confused 40 years ago, is now rare in North America and is usually associated with use of the trivalent oral vaccine or travel to areas where poliomyelitis is endemic. Patients with poliomyelitis usually present with fever, meningeal signs, asymmetric weakness, and a predominance of lymphocytes in the cerebrospinal fluid, all of which are absent in patients with tick paralysis.
Botulism, with which tick paralysis can also be confused, is characterized by a slow, descending paralysis that involves the cranial nerves first, usually with extraocular palsy and large, poorly reactive pupils, unlike the rapid, ascending pattern of tick paralysis.9
Neurotoxin produced by the Ixodes holocyclus tick, found in Australia, interferes with acetylcholine release at the neuromuscular junction, as does botulinum toxin.9,11,20 Extracts of homogenized I. holocyclus ticks produce paralysis when injected in dogs.21 The neurologic impairment caused by I. holocyclus ticks in Australia is more severe than that caused by dermacentor species in North America. With exposure to I. holocyclus neurotoxin, the weakness and bulbar symptoms often intensify during the first 24 to 48 hours after the tick has been removed, and clinical recovery is much slower than with dermacentor-related paralysis. For these reasons, I. holocyclus antitoxin must be administered before the tick is removed, and longer observation is required.20
The onset of tick paralysis occurs five to seven days after a female tick attaches itself to the skin. Engorgement of the feeding tick is relatively limited until it mates with a male. Mating leads to rapid engorgement, the fertilization of eggs, and the production of neurotoxin. The term "ixovotoxin" has been applied to the substance responsible for the development of tick paralysis.22 The beginning of neurotoxin production coincides with the initial paralytic symptoms in affected patients. Continued feeding by the tick apparently accelerates toxin production, accounting for the rapid clinical deterioration. Once engorgement is complete, the female tick disengages from its host and drops off to deposit the eggs. The D. variabilis tick removed from our patient deposited approximately 200 eggs 17 days after removal, an observation that supports prior claims that the fertile dermacentor female causes tick paralysis in the United States.23,24
Removal of the embedded tick usually results in resolution of symptoms within several hours to days. If the tick is not removed, the toxin can be fatal, with reported mortality rates of 10–12 percent,[4] usually due to respiratory paralysis. The tick is best removed by grasping the tick as close to the skin as possible and applying firm steady pressure.[5]
Which of the following findings is NOT likely to be seen on analysis of the cerebrospinal fluid (CSF) of a patient with Guillain-Barré syndrome who has had symptoms for 3 weeks?
Your Colleagues Responded: Elevated opening pressuresCorrect Answer 75% Fewer than 10 white blood cells per high power field (typically mononuclear) 6% Elevated protein concentration (usually greater than 45 mg/dL) 8% Normal glucose concentration 8%
Which of the following symptoms is NOT associated with a progression to respiratory failure in children with the above presentation?
Your Colleagues Responded: Rapid disease progression 5% Bulbar dysfunction 8% Absent deep tendon reflexes in the lower extremitiesCorrect Answer 63% Dysautonomia 16% Pharyngeal dysfunction with loss of the gag reflex 6%
Approximately 20% of children with Guillain-Barré syndrome require mechanical ventilation for respiratory failure; the need for intubation should be anticipated early so that it can be done electively. Progression to respiratory failure has been predicted in patients with rapid disease progression, bulbar dysfunction, bilateral facial weakness, or dysautonomia, and emergent intubation should be performed in any patient with loss of the gag reflex, declining respiratory function, or pharyngeal dysfunction. There has been no correlation between loss of deep tendon reflexes in the lower extremities and the need for intubation and mechanical ventilation.
Table 187-1. Causes of MicrocephalyPrimary MicrocephalyMicrocephaly veraChromosomal disorders Trisomy 21 Trisomy 13 Trisomy 18 5P- Angelman syndrome Prader-Willi syndromeCNS malformation Holoprosencephaly Encephalocele HydranencephalyCNS migrational disorder Lissencephaly Schizencephaly Pachygyria Micropolygyria Agenesis of the corpus callosumSex-linked microcephalySyndromes Smith-Lemli-Opitz syndrome Cornelia de Lange syndrome Seckel dwarfism syndrome Cockayne syndrome Rubinstein-Taybi syndrome Hallermann-Streiff syndromeSecondary (Acquired) MicrocephalyInfections (congenital) Rubella Cytomegalovirus Toxoplasmosis Syphilis HIVInfections (noncongenital) Meningitis EncephalitisStrokeToxic Radiation of the fetus Fetal alcohol syndrome Maternal phenylketonuriaHypoxic-ischemic or other severe brain injury Periventricular leukomalaciaSystemic disease Chronic cardiac or pulmonary disease Chronic renal disease MalnutritionCraniosynostosis totalis