CHANCROID

Q. A 30-year-old sexually active woman presents with a painful vesicle on her external genitalia and bilateral inguinal lymphadenopathy. A Tzanck smear from the vesicle fails is negative, and polymerase chain reaction analysis of viral DNA is negative. A VDRL assay is also negative. Which of the following medications would be most helpful to this patient?
(A) Acyclovir
(B) Ceftriaxone
(C) Foscarnet
(D) Ribavirin
(E) Vancomycin


Ans:   B.  
The differential diagnosis of a genital ulcer in a sexually active patient should include primary syphilis (though these ulcers are usually painless), genital herpes, and chancroid. 
Because the Tzanck smear (which looks for multinucleated giant cells typical of herpes infection), viral polymerase chain reaction (used to look for herpesvirus) are both negative, as is the VDRL to test for syphilis, chancroid becomes most likely. 

Chancroid is a bacterial infection caused by Haemophilus ducreyi, which presents typically as a painful genital ulcer with associated inguinal lymphadenopathy. It is typically treated with ceftriaxone, though azithromycin or ciprofl oxacin can be used. Vancomycin is effective only

for gram-positive organisms

 A is incorrect. Acyclovir is used to treat herpes infections. It is activated by viral thymidine kinase, whereupon it inhibits the herpes viral polymerase. It can be used to treat herpes simplex virus (HSV) types 1 and 2, varicella- zoster virus (VSV), and Epstein-Barr virus (EBV) infections. It is not effective for bacterial organisms.

 C is incorrect. Foscarnet inhibits viral DNA polymerase without the need of activation by thymidine kinase. It is used to treat cytomegalovirus (CMV) retinitis, but it can also be used

to treat acyclovir-resistant HSV.

 D is incorrect. Ribavirin is used to treat respiratory syncytial virus. It functions by inhibiting inosine monophosphate dehydrogenase, thus blocking the synthesis of guanine

nucleotides.

 E is incorrect. Vancomycin is a bactericidal antibiotic used for multidrug-resistant gram-positive organisms such as Staphylococcus aureus and Clostridium diffi cile. It functions

by binding to mucopeptide precursors, preventing formation of the bacterial cell wall

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.

WPW, AD & ATAXIA

Q. DOC for a pateint with Wolf-Parkinson-White syndrome ...
a) Procainamide
b) Disopyramide
c) Quinidine
d) Amiodarone

Ans:  a) Procainamide

Treatment: Accessory Pathway-Mediated Tachycardias

 " In life-threatening situations, DC cardioversion should be used to terminate the AF. In nonlife-threatening situations, procainamide at a dose of 15 mg/kg administered IV over 20–30 min will slow the ventricular response and may organize and terminate AF. Ibutilide can also be used"

Ref: Harrison Internal Medicine 18 th ed.



Q. An 84 year old woman with Alzheimer's dementia has recently become incontinent and more confused than usual. What is the diagnosis?
a) Detrusor overactivity
b) Neuropathic bladder
c) Nocturnal enuresis
d) Urinary tract infection
e) Uterine prolapse

Ans:  d) Urinary tract infection

UTI is very common in Alzheimer disease that results in sudden deterioration of consciouslevel. Patient may beome profoundly confused.
Neuropathic bladder do not results in confusion.


Q. A 38 year old man with longstanding alcohol dependence has vertigo and a tremor every morning. What is the diagnosis?
a) Anxiety
b) Benign positional vertigo
c) Cerebellar degeneration
d) Optic neuritis
e) Temporal lobe epilepsy

Ans: cerebellar degeneration

In patients with alcohol-related ataxia, the symptoms affect gait and lower limbs more than arms and speech, often also with signs of peripheral neuropathy. The ataxia can stabilise or even improve with stopping alcohol, but worsen in those who continue. Brain imaging typically shows vermis atrophy.
Alcohol is directly toxic to the cerebellum, causing degeneration of the anterior superior vermis and hemispheres. 

ANTICONVULSANTS

ANTICONVULSANTS:

Q. A 35-year-old woman, recently diagnosed with simple partial seizures, started the prescribed therapy. Her past history was unremarkable, but her mother was known to suffer from acute intermit tent porphyria. Which of the following anticonvulsant drugs would be appropriate for this patient?
A. Diazepam
B. Ethosu ximide
C. Valproic acid
D. Carbamazepine
E. Phenytoin
F. Lamotrigine

Ans:  F.  Lamotrigine

Explanation:  Lamotrigine is effective in simple partial seizures, as well as in generalized tonic-clonic and absence seizures. It appears to have comparable effectiveness with more traditional anticonvulsant drugs, such as valproic acid, carbamazepine, and phenytoin. The primary mechanism of action of lamotrigine most likely includes a frequency-dependent blockade of voltage-gated Na+ channels. C−E Valproic acid, carbamazepine, and phenytoin are firstchoice drugs in partial seizures, but they are contraindicated when there is a risk of acute intermittent porphyria, because they can trigger an attack. Because acute intermittent porphyria is an autosomal disorder, it is bet ter to avoid these drugs in patients whose parents are known to suffer from the disease, as in this case. A, B Diazepam and ethosuximide are not effective in simple partial seizures.

Q. A 53-year-old man suffering from partial seizures had been receiving a high dose of carbamazepine for 6 months. Which of the following dose-related adverse effects most likely occurred during the therapy?
A. Gingival hyperplasia
B. Hallucinat ions
C. Ataxia
D. Stevens−Johnson syndrome
E. Heart failure
F. Dilut ional hyponatremia

Ans: C. Ataxia

Explanation: Some of the adverse e ects of carbamazepine are related to cerebellar-vestibular impairment. The most common  dose-related adverse effect of this kind is ataxia (up to 15%

of patients). A This would be an adverse e ect of phenytoin. It does not occur with carbamazepine. B, D−F All these are serious but quite rare adverse effects of carbamazepine.

 
Q. A 24-year-old woman with a long history of absence seizures had been successfully managed with valproic acid for the past 5 years. The patient had recently married, and during her last visit she expressed the desire to start a family. Which of the following drugs would be most appropriate for this patient to substitute for valproic acid therapy?
A. Carbamazepine
B. Clonazepam
C. Phenytoin
D. Ethosuximide
E. Phenobarbital
F. Tiagabine

Ans: D. Ethosuximide

Explanation: Valproic acid is classified by the U.S. Food and Drug Administration as pregnancy category D because it increases the 
 risk of neural tube defects (up to 20-fold) when given during pregnancy. Ethosuximide is instead classi ed as pregnancy category C and is a rst-line drug for absence seizures. A−C, E, F These drugs are not effective (and some of them can even be dangerous) in absence seizures.