Name the most common neuromuscular junction disease seen on the medical ward. Summarize its prevalence and distribution.
Myasthenia gravis (MG). MG has a prevalence of 1 case/10,000 population and a bimodal age distribution, occurring in young women in their teens and 20s and older men aged 60 and above.

What causes MG?
MG is an autoimmune disease in which patients produce antibodies that destroy the acetylcholine receptors on muscle. Acetylcholine is the neurotransmitter that makes muscles contract.

How does MG present?
MG presents with proximal weakness, especially ptosis and diplopia, with fatigue on use and recovery with rest. Because MG can involve the respiratory muscles, pulmonary failure is the most feared complication.

How is MG treated?
Treatment consists of acetylcholinesterase inhibitors, which block the enzymatic breakdown of acetylcholine, thus allowing greater concentrations of acetylcholine at the receptor. Pyridostigmine (Mestinon) is the drug of choice, but immunosuppressive drugs, including prednisone, azathioprine, and cyclosporine, are often necessary to attack the underlying autoimmune process. Plasmapheresis and IVIG have also been shown to help. Surgical thymectomy is probably beneficial, but its role in treating MG remains controversial. Read the rest of this entry »

Which tests and procedures are used in the diagnostic evaluation of a patient with a suspected myopathy?
The diagnostic evaluation of a myopathy generally entails a triad of tests:

• Serum creatine kinase (CK)
• Electromyography (EMG)
• Muscle biopsy

Explain the significance of serum CK.
Muscle destruction usually liberates CK, making elevation of this enzyme a good screening test for muscle disease. (The MM isoenzyme of CK is the most common.)

What can you learn from the EMG?
An EMG is done by inserting a fine-needle electrode into the muscle to record the electrical impulses related to contractions. Myopathies cause low-voltage, short-duration muscle contractions, and this test can thus confirm the presence of myopathy. Read the rest of this entry »

Define somatization disorder.
According to the DSM-IV, it is a psychiatric condition characterized by multiple, recurrent physical complaints for which no organic basis can be found. The disorder begins before age 30 and is more common in females. Common physical complaints include vomiting, pain in the extremities, shortness of breath, amnesia, pain in the sexual organs or rectum, and dysmenorrhea. The patient makes frequent visits to physicians because of the physical symptoms, and internists often see and evaluate these patients.

How should the internist approach the patient with somatization disorder?
Because the cycle in somatization disorder (or any somatoform disorder) often is physical complaint → unrevealing work-up → empiric therapy → unsatisfying outcome → return to doctor, the danger of iatrogenic disease is quite real. The physician who can establish a long-lasting relationship with the patient is occasionally able to break the cycle with good history-taking and examination skills and diagnostic and therapeutic restraint. Even more important is that the patient trusts the physician-often patients develop substantial mistrust of health care providers after repeated encounters are fruitless and they are labeled “crocks.” A dedicated primary care physician may be able to identify underlying emotional or mental health issues (e.g., sexual abuse) that may be amenable to psychiatric consultation and treatment. The treating physician should express empathy for the patient, acknowledging the patient’s difficulties and challenges, and a commitment to helping the patient cope with his or her symptoms.

What is a personality disorder?
A personality disorder is an enduring pattern of maladaptive behavior that interferes with a person’s ability to achieve success and satisfaction in interpersonal and work relationships. Patients with personality disorders meeting DSM-IV criteria more frequently sustain injuries, attempt suicide, abuse substances, and have poorer outcomes for depression treatment than the general population.

Define the three groups of personality disorders.
The DSM-IV divides 10 personality disorders into three groups:
• Cluster A: “odd or eccentric” (paranoid, schizoid, schizotypal)
• Cluster B: “dramatic” (histrionic, narcissistic, borderline, antisocial)
• Cluster C: “anxious” (avoidant, dependent, obsessive-compulsive)

When should a clinician suspect that a patient has a personality disorder?
Such patients often pose severe challenges to a physician’s professionalism and empathy. They often do not see a connection between their behavior and its outcomes, and pointing out such relationships can lead to considerable anger. It may be impossible to establish a mutually satisfying patient-physician relationship; the patient alternates between glowing approval and open distrust of the physician. A physician’s own discomfort within a particular patient-physician relationship may signal the presence of a personality disorder. Patients with severe behavioral difficulties should be referred to mental health professionals for treatment. In addition, patients presenting with depression or anxiety disorders who also have symptoms suggestive of a coexistent personality disorder should be referred to mental health professionals, because the personality disorder frequently complicates the treatment of the mood disorder. Read the rest of this entry »

What are the important issues in the preoperative care of patients with a permanent cardiac pacemaker?
Pacemakers and implantable cardioverter/defibrillators (ICDs) should be evaluated before any operation in which electrocautery is used. Two issues must be addressed: the cardiac status of the patient, including assessment of adequacy of pacemaker function, and safety in the operating room. In general, the adequately functioning pacemaker (1) senses the patient’s own intracardiac signals and (2) delivers an electric stimulus to depolarize the myocardium at a time when it is excitable and at an appropriate rate. Pacemaker function should be assessed during the month before elective surgery at the usual source of pacemaker care.

How do you manage the problem of electromagnetic interference in the operating room?
In the operating room, electromagnetic interference (usually from electrocautery) may cause failure of the demand pacemaker. This problem can be solved by converting the pacemaker from a demand mode to a fixed-rate mode by placing a high-powered magnet over the generator. The possibility of electromagnetic interference can be minimized by placing the ground plate as far from the generator as possible and by using electrocautery in short bursts. In patients with a temporary pacemaker, the pacemaker leads provide a direct pathway by which extraneous external electrical impulses can go directly to the heart. The contact points between the leads and the generator should be covered with a surgical glove, and gloves should be worn when the unit is handled. The pacemaker/ICD should be evaluated again after the procedure. Similar precautions should be taken for patients with these devices who receive radiotherapy or lithotripsy. Read the rest of this entry »

What are the four essential “dos” of preoperative risk assessment?

• Do interview and examine the patient with respect to major organ-system disease, and describe the extent, severity, and stability of each disease in your assessment.
• Do explain to the patient your estimate of his or her risk of complications of anesthesia and surgery, and document the explanation in your consultation note.
• Do specify how the patient’s current medications should be handled in the perioperative period.
• Do make recommendations for venous thromboembolism prophylaxis in patients who may benefit.

List the three essential “don’ts” of preoperative risk assessment.

• Don’t tell the anesthesiologist which type of anesthesia and anesthetic agent to use; this determination is the anesthesiologist’s job. The anesthesiologist relies on you for adequate characterization of the patient’s burden of medical disease.
• Don’t “clear” the patient for surgery-such a step implies complete freedom from risk of adverse events, and we can never guarantee that a patient will not suffer an adverse outcome.
• Don’t directly try to change a patient’s mind about proceeding with surgery-you are interfering in a patient-doctor relationship! Encourage patients to ask the surgeon questions about the proposed procedure. If you have serious concerns about surgery for a particular patient, call the referring surgeon and speak with him or her in a confidential manner and setting.

Describe general anesthesia (GA).
GA provides a loss of sensation with the loss of consciousness. Patients under GA may receive inhaled agents, inhaled plus IV drugs, or IV drugs alone. Ventilation may be managed through a mask, with or without an oropharyngeal or laryngopharyngeal airway, or through an endotracheal tube.
KEY POINTS: PURPOSE OF THE PREOPERATIVE RISK ASSESSMENT
1. Describe the patient’s current chronic diseases, their management, the patient’s level of symptomatology, and whether the diseases are stable.
2. Make an estimate of the patient’s risk of postoperative cardiac and noncardiac complications. Read the rest of this entry »

Define the risk groups on which current recommendations for cervical carcinoma screening are based.
Recommendations concerning periodic screening of women in the U.S. using Pap smears (Papanicolaou-Traut smears) have been developed for the various risk groups. Low-risk groups are those women who have never had sexual activity, have had a hysterectomy for nonmalignant reasons, or have reached the age of 60 and have never had a positive Pap smear. High-risk patients are those who are sexually active early, have had many partners, or are in low socioeconomic groups.

What are the current recommendations for cervical carcinoma screening.
The American Cancer Society and the American College of Obstetricians and Gynecologists recommend that asymptomatic women over 18 years of age and those under age 18 who are sexually active have annual screening for at least 3 years initially. Some groups recommend that women then be screened every 2-3 years until age 65, while others suggest yearly screening as long as the patient is sexually active. High-risk patients should be screened yearly.

Sumarize the appropriate management of a patient with an abnormal Pap smear.
A persistently abnormal Pap smear should lead to colposcopy and/or biopsy.

What should be done if carcinoma in situ or dysplasia is found?
Cryotherapy, laser therapy, cone biopsy, or hysterectomy should be performed, depending on the size and extent of the lesion. Read the rest of this entry »

Who gets esophageal cancer?
Squamous cell cancer of the esophagus occurs in the 40- to 60-year-old age group and is seen mainly in men. The incidence is increased in Africa, China, Russia, Japan, Scotland, and the Caspian region of Iran. In the U.S. the nonwhite male population is at increased risk. Adenocarcinoma of the esophagus tends to occur in obese white men.

List the risk factors for esophageal cancer.

• Excessive alcohol and/or tobacco use
• Native Bantu beer (southern Africa)
• Chronic hot beverage ingestion
• Lye ingestion: > 30% of cases develop esophageal cancer
• Tylosis: > 40% of cases develop esophageal cancer
• Achalasia
• Plummer-Vinson syndrome
• Nontropical sprue
• Prior oral and pharyngeal cancer
• Occupational exposure to asbestos, combustion products, ionizing radiation
• Other occupational exposure: waiters, bartenders, metal workers, and construction workers
• Decreased dietary intake of fruits and vegetables throughout adulthood Read the rest of this entry »