GIANT CELL ARTERITIS (TEMPORAL ARTERITIS)

GIANT CELL ARTERITIS OF THE ELDERLY
(TEMPORAL ARTERITIS)


Giant cell arteritis (GCA) is a large vessel vasculitis that primarily affects white patients over the age of 50, often affecting the extracranial arteries.
Patients frequently manifest new onset of headache, which is continuous, scalp or temporal artery tenderness, jaw claudication, visual disturbances, fatigue, and arthralgias.
 Patients can have an insidious or explosive onset of disease and can manifest primarily cranial or constitutional symptoms.
Blindness occurs in about 15% of patients with GCA, even with appropriate therapy, and can occur at disease onset.


The diagnosis of GCA should be confirmed with a superficial temporal artery biopsy. Whether or not bilateral biopsies should be obtained initially remains an area of controversy, because a few cases have been reported in which the symptomatic temporal artery biopsy was negative but the
asymptomatic contralateral artery demonstrated arteritis.
Anemia and elevated acute phase reactants are commonly seen in patients with GCA.
Large vessel disease, similar to that seen in TA, has been reported in GCA. Aortitis is one of the most common manifestations of large vessel involvement in patients with GCA and leads to an increased risk of aortic aneurysm and subsequent dissection and rupture. Given this potential catastrophic complication, it has been suggested that GCA patients undergo yearly surveillance with chest radiography to look for aortic enlargement, but the potential impact of this intervention on outcomes in GCA remains speculative.


Glucocorticoids are the cornerstone of therapy in GCA. Patients often experience disease relapses with steroid tapering, but other immunosuppressive agents overall have not demonstrated steroid-sparing activity in GCA. Although many patients with relapsing disease are still given trials of
other immunosuppressive agents, given the toxicities associated with long-term steroid use, most patients continue to require steroid therapy for maintaining disease remission.


Polymyalgia rheumatica (PMR), a syndrome characterized by pain and stiffness in the muscles of the neck, shoulder girdle, and hip girdle with other signs and symptoms of systemic inflammation, is associated with GCA. However, not all patients with GCA manifest PMR symptoms, and not
all patients with PMR develop GCA. However, because the prevalence of GCA is higher in patients with PMR, they should be educated regarding signs and symptoms of GCA.

CALCIFIED MASS

Q.A 35-year-old woman has noticed that over the past 3 to 5 months she has had some difficulties with balance, particularly when she closes her eyes. On examination, she has decreased hearing in her left ear and also left body dysdiadochokinesia. Her physician orders a head CT. Given this CT scan, which was obtained without contrast enhancement, the physician must assume that the posterior fossa mass at the arrow is-
a. Normal
b. Calcified
c. Highly vascular
d. Granulomatous
e. Highly cystic

Ans: b. calcified.
Exp:

Calcified masses appear hyperdense without contrast enhancement,

 whereas highly vascular lesions may

appear dense on CT scanning after the patient has received intravenous contrast material. Tumors, granulomas, and other intracranial lesions enhance

because of a breakdown in the blood-brain barrier. More cystic lesions may

exhibit enhancement limited to the periphery of the cyst.



Q. If a patient exhibits café au lait spots and reports a family history of bilateral hearing loss at a relatively young age, a gene abnormality should be suspected on chromosome-
a. 5
b. 13
c. 17
d. 21
e. 22 

Ans: e. 22.
Exp:

Meningiomas occur with increased frequency in type 2 neurofibromatosis, a dominantly inherited disorder arising

with a deletion on the long arm of chromosome 22. Women with breast

cancer and other gynecologic cancers are also at increased risk of developing

meningiomas, perhaps because of sex steroid receptors on these tumors

that enhance their growth when gynecologic disturbances occur. Estrogen

or progesterone antagonists may be useful in the management of these

tumors, but tamoxifen, an estrogen inhibitor, paradoxically stimulates the

growth of meningioma cells .

ENG, PM & Nystagmus

A 25-year-old woman with a history of epilepsy presents to the emergency room with impaired attention and unsteadiness of gait. Her phenytoinnlevel is 37. She has white blood cells in her urine and has a mildly elevated TSH. Examination of the eyes would be most likely to show which of the following?
a. Weakness of abduction of the left eye
b. Lateral beating movements of the eyes
c. Impaired convergence
d. Papilledema
e. Impaired upward gaze

Ans: B.

Most rhythmic to-and-fro movements of the eyes are called nystagmus. Nystagmus has a fast component in one direction and a slow component in the opposite direction. Nystagmus with a fast component to the right is called right-beating nystagmus.

 Phenytoin (Dilantin) may evoke nystagmus at levels of 20 to 30 mg/dL. The eye movements typically appear as a laterally beating nystagmus on gaze to either side; this type of nystagmus is called gaze-evoked. If the patient has nystagmus on looking directly forward, he or she is said to have nystagmus in the position of primary gaze. 

Therapeutic levels for phenytoin are usually 10 to 20 mg/dL, and some patients develop asymptomatic nystagmus even within that range. Ataxia, dysarthria, impaired judgement, and lethargy may also occur at toxic levels of phenytoin.

 Many other drugs also evoke nystagmus. Weakness of abduction of the left eye, or abducens palsy, is due either to injury to the sixth cranial nerve or to increased intracranial pressure. Impaired convergence can occur normally with age or may be a sign of injury to the midbrain. Papilledema is a sign of increased intracranial pressure. Impaired upward gaze may occur in many conditions, but would not be expected to occur with a toxic phenytoin level.

Q.  A 75-year-old generally healthy man has noticed worsening problems maneuvering over the past 4 months. He has particular trouble getting out of low seats and off toilets. He most likely has which of the following?
a. Poor fine finger movements
b. Poor rapid alternating movements
c. Distal muscle weakness
d. Proximal muscle weakness
e. Gait apraxia

Ans: d.

With primary muscle diseases, such as polymyositis, weakness usually develops in proximal muscle groups much more than in distal groups. This means that weakness will be most obvious in the hip girdle and shoulder girdle muscles. The hip girdle is usually affected before the shoulder girdle. To get out of a low seat, the affected person may need to pull him- or herself up using both arms. Persons with more generalized weakness or problems with coordination are less likely to report problems with standing from a seated position. Poor rapid alternating movements and poor fine finger movements usually develop with impaired coordination, such as that due to cerebellar damage.

With severe weakness in the limbs, patients will do poorly on these tests of function as well. With proximal muscle weakness, the affected person will usually perform relatively well on these tests of distal limb coordination.

Q.  A 67-year-old woman says that she is having problems with dizziness. A more careful history reveals that she has an abnormal sensation of movement intermittently. Which of the following tests would be most helpful in determining the cause of episodic vertigo?
a. CSF
b. C-spine MRI
c. Visual evoked response (VER)
d. Electronystagmography (ENG)
e. Electroencephalography (EEG)

Ans: d. 

 ENG is used primarily to characterize nystagmus and disturbances of eye movements that involve relatively fast eye movements. Abnormal patterns of eye movement may help localize disease in the central or peripheral nervous system in patients with vertigo. The retina is negatively charged in comparison with the cornea, which creates a dipole that is monitored during ENG studies by electrodes placed on the skin about the eyes. Movement of the most posterior elements of the retina toward an electrode is registered as a negative voltage change at that electrode. Damage to the pons may produce characteristic conjugate deviations of the eyes. The conjugate eye movements are rhythmic and directed downward, but they lack the rapid component characteristic of nystagmus. This type of abnormal eye movement is called ocular bobbing. A lesion at the cervicomedullary junction, such as a meningioma at the foramen magnum, will produce a down-beating nystagmus with both eyes rhythmically deviating downward, with the rapid component of this nystagmus directed downward as well. Cervicomedullary refers to the cervical spinal cord and the medulla oblongata. Damage to the midbrain, thalamus, or hypothalamus may disturb eye movements, but down-beating nystagmus would not ordinarily develop with damage to these structures.