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Aortic regurgitation is characterize by a diastolic murmur that gradually decreases in intensity . Aortic regurgitation can be caused by reactive arthritis, ankylosing spondylitis, Marfans syndrome and syphilis. His high degree of sexual activity, painless genital ulcer and lymphadenopathy should raise suspicion for Syphilis as underlying his aortic regurgitation. Cardiac and neural involvement is seen in tertiary syphilis. Tertiary syphilis is treated with intravenous penicillin and desensitization in penicillin sensitive patients
'''Educational Objective:''' Syphilis in its tertiary phase can involve the aortic valve, thereby causing aortic regurgitation.,
'''References:''' References: Page 17,18,64 Master the boards step 3 2009 edition, Page 91,92 Master the boards Step 2 CK second edition<br/>
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Aortic regurgitation can be caused by reactive arthritis, ankylosing spondylitis, marfans syndrome and syphilis. Features of aortic regurgitation include diastolic decrescendo murmur at lower left sternal border, head bobbing with each pulse, Capillary pulsations in the finger nails, murmur over femoral artery , and high bounding pulse. . Transthoracic echocardiogram is the best initial diagnostic test for all valvular diseases. In aortic regurgitation angiotensisn converting enzyme inhibitors, angiotenisn receptor blockers and nifedipine are the best initial therapy but surgery is when ejection fraction drops below 55% and left ventricular end systolic diameter is more than 55mm.
'''Educational Objective''' In aortic regurgitation angiotensisn converting enzyme inhibitors, angiotenisn receptor blockers and nifedipine are the best initial therapy but surgery is essential when ejection fraction drops below 55% and left ventricular end systolic diameter is more than 55mm.
'''References''' Page 64,66 Master the boards step 3 2009 edition, Page 91 Master the boards Step2 CK second edition<br/>
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Arachnodactyly (spider fingers) are long slender fingers as shown in the image, a feature of some connective tissue diseases Marfans syndrome being one of them. Unusually lengthy arms, flat feet and scoliosis are also associated with Marfans syndrome. In this patient echocardiography showed a valve regurgitation and a diastolic murmur could be heard at the lower left sterna border, that suggests aortic regurgitation. Marfans syndrome is one of the causes of aortic regurgitation along with reactive arthritis, ankylosing spondylitis and syphilis. This patient most likely has aortic regurgitation secondary to marfans syndrome. All the features given in the options are features of aortic regurgitation except hoarseness of the voice which is seen in mitral stenosis due to compression of the recurrent laryngeal nerve.
'''Educational Objective:''' Hoarseness of the voice is not seen in aortic regurgitation. It is a feature of mitral stenosis where an enlarged left atrium presses on recurrent laryngeal nerve to produce a hoarse voice.
'''References:'''Page 91 Master the boards step 2 CK second edition, Page 64 Master the boards step 3 2009 edition, http://www.wikidoc.org/index.php/Marfan%27s_syndrome_pathophysiology William James Gibson, C. Michael Gibson, M.S., M.D. 14:38, 22 August 012, http://www.wikidoc.org/index.php/Arachnodactyly<br/>
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This patient in this scenario is experiencing classical symptoms of perimenopause including mood swings, irritability, and irregular and lengthy cycles. Other typical symptoms are similar to those seen during menopause and may include: depression, fatigue, hot flashes, night sweats, and vaginal dryness. The main defining factor that distinguishes the perimenopausal period from menopause is the cessation of menstruation for a period of 12 months, as well as a significant drop in estrogen levels. In premenopause, estrogen levels are mildly greater than in premenopausal women. Initially, the reduced quantity and quality of ovarian follicles leads to lower baseline estrogen levels that trigger a positive feedback increase in GnRH, FSH and LH. This rise causes increased estrogen secretion by the still functional ovaries. During menopause, this increase in gonadotropins does not affect estrogen levels due to the inability of the ovaries to produce estrogens.<br/>
'''Educational Objective:''' Perimenopause defines the time frame preceding menopause that may be characterized by irregular cycles, and certain symptoms of menopause. Classically gonadotropins are increased and estrogens are higher than normal levels in premenopausal women. The main defining factor that distinguishes the perimenopausal period from menopause is the cessation of menstruation for a period of 12 months, as well as a significant drop in estrogen levels.<br/>
'''References:''' Santoro N, Brown JR, Adel T, Skurnick JH. Characterization of reproductive hormonal dynamics in the perimenopause. J Clin Endocrinol Metab. 1996;81(4):1495-501. +
Polyarteritis nodosa (PAN) is a vasculitis that mainly affects the small and medium-sized arteries, particularly the at the level of the kidneys, heart, and GI tract. Classical symptoms are non-specific and include fever, malaise, anorexia, weight loss, and myalgias. Physical examination is often remarkable for soft tissue edema, rashes (livedo relicularis; lace like rash shown in this patient), petechiae, and ulcerations. Depending on the involved system, manifestations include numbness and paresthesias, strokes, seizures, renal insufficiency, myocardial infarction or pericarditis. Approximately 25% of patients with PAN have positive a hepatitis B serum antigen. In fact, according to the American College of Rheumatology (ACR) diagnostic criteria, hepatitis B status is taken into consideration. Diagnosis is generally based on the clinical picture, laboratory studies (CBC, ESR, C-reactive protein, p-ANCA), and biopsy. Treatment involves the use of immunosuppressants – prednisone, cyclophosphamide and methotrexate.<br/>
'''Educational Objective:''' Polyarteritis nodosa is a vasculitis involving the small and medium sized arteries, particularly the renal, cardiac, and gastrointestinal tract vessels. One of the classical features is the characteristic lace-like rash known as livedo reticularis. PAN is associated with hepatitis B infection.<br/>
'''References:''' Ahmed S, Kitchen J, Hamilton S, Brett F, Kane D. A case of polyarteritis nodosa limited to the right calf muscles, fascia, and skin: a case report. J Med Case Rep. 2011;5:450.'''(Image)''' +
The patient has the typical presentation of a biliary colic with physical exam suggestive of cholecystitis (Murphy's sign is positive). Murphy's sign is assessed by asking the patient to inhale deeply while the approximate location of the gallbladder is palpated (right upper quadrant, midclavicular line). As the patient inhales and pushed the bowel contents down, the pressure exerted on the inflamed gallbladder causes the patient to stop breathing suddenly. The air that was observed in the biliary tree on cholangiogram is indicative that a large gallbladder stone has likely created a fistula between the gallbladder and the small intestine allowing it to escape. Classically, if the stone is large enough, it would obstruct the narrowest part of the intestinal lumen, usually the ileocecal valve. Obstruction would cause a syndrome of ileus with bloating, nausea and vomiting, and obstipation known as gallstone ileus. Treatment is usually surgical. Despite treatment, mortality can be as high as 30% of patients affected.<br/>
'''Educational Objective:''' Large biliary stones can create a fistula between the gallbladder and duodenum and block the ileocecal valve leading to gallstone ileus.<br/>
'''References:''' Reisner RM, Cohen JR. Gallstone ileus: a review of 1001 reported cases. Am Surg. 1994;60(6):441-6. +
It is a typical presentation of Mallory-Weiss syndrome which is characterized by blood in vomiting due to mucosal tears at junction of oesophagus and stomach. Most common precipitating factors are retching, forceful vomiting due to excessive alcohol use, alcohol binge, hiatal hernia and eating disorders. Endoscopy is the first investigation of choice and further management depends on endoscopic findings. However, before endoscopy is done, IV fluids should be administered in any hemodynamic unstable patient.<br/>
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Primary biliary cirrhosis (PBC) is a slowly progressive autoimmune hepatic pathology. It is characterized by the presence of portal inflammation and intrahepatic bile duct destruction that is immune-mediated. Eventually, loss of bile ducts lead to diminished secretion of toxic compounds that are retained in the liver and ultimately cause hepatic failure.
The prevalence of PBC differs from one region to another; it is most prevalent in Northern Europe. Several environmental factors have been hypothesized to be associated with PBC such as infectious etiologies (E. coli and N. aromaticivorans) and exposure to chemicals or pesticides. Genetic predisposition my also play a role.
PBC may be associated with other autoimmune diseases, such as Hashimoto's hypothyroidism. It is a common disease among middle-aged female patients and very uncommon in childhood and early adulthood. Antimitochondrial antibodies are found in more than 90% of patients and may be elevated even prior to the onset of symptoms. Fatigue and pruritis are the most common clinical presentations, but it is noteworthy to mention that more than 50% of patients are asymptomatic. Physical examination findings of jaundice, xanthelesma, and hepatomegaly are classical, but may not always be present or may become apparent late during the disease progression. Early diagnosis and management are important for prognosis, which may be very poor if not treated. Complications of PBC include: osteoporosis, hyperlipidemia, portal hypertension, annd fat-soluble vitamin deficiency. Treatment options include ursodeoxycholic acid, colchicine, and methotrexate. The only effective treatment, however, is liver transplantation with recurrence rates reaching 15% within 3 years and 30% within 10 years.<br/>
'''Educational Objective:''' Primary biliary cirrhosis is characterized by the presence of asymmetric destruction of the interlobular bile ducts.<br/>
'''References:''' Marshall KM, Gershwin ME. Primary biliary cirrhosis. N Engl J Med. 2005; 353:1261-1273.
The patient is presenting with symptoms and signs consistent with Hashimoto's thyroiditis. She reports excessive fatigue, sleepiness, weight gain, cold intolerance, hair loss, and constipation - all of which are symptoms of hypothyroidism. Furthermore, physical examination confirms a thyroid pathology; and work-up makes the diagnosis of Hashimoto's thyroiditis most likely due to the presence of anti-TPO (positive in 90% of Hashimoto's thyroiditis cases). Hashimoto's thyroiditis is known to be associated with Non-Hodgkin's lymphoma (NHL). The most common form of thyroid NHL in patients with Hashimoto's thyroiditis is a low grade B-cell lymphoma of MALT type. Thyroid NHL is 4 times more common in women than in men, and up to 50% of the these patients have a history of Hashimoto's thyroiditis. The most common clinical manifestations are related to a rapidly the rapidly enlarging mass and include progressive goiter and compression symptoms.<br/>
'''Educational Objective:''' Hashimoto's thyroiditis is associated with Non-Hodgkin's lymphoma.<br/>
'''References:''' Scholefield JH, Quayle AR, Harris SC, Talbot CH. Primary lymphoma of the thyroid, the association with Hashimoto's thyroiditis. Eur J Surg Oncol. 1992;18(2):89-92. +
Cardiogenic pulmonary edema is one of the main manifestations of fluid transudation due to increased hydrostatic pressure. Transudates can be distinguished from exudates by their hypo cellular and protein-poor fluid. Accordingly, they have low specific gravities, usually < 1.015. Cardiogenic edema is due to elevated hydrostatic pressures and low oncotic pressures. In contrast, exudates are cellular, protein-rich fluids that have high specific gravities, usually > 1.015. They are commonly caused by lymphatic obstruction and inflammation. Transudation may occur into the parenchyma leading to pulmonary edema or the pleura leading to pleural effusion.<br/>
'''Educational Objective:''' Cardiogenic edema is associated with transudative fluid and low oncotic pressure and high hydrostatic pressure.<br/>
'''References:''' Kumar V, Abbas AK, Aster JC. Robbins Basic Pathology. Chapter 2: Inflammation. Elsevier Health Sciences; 2012. +
Squamous cell carcinoma (SCC) of the bladder is caused by chronic granulomatous inflammation of the bladder that eventually leads to metaplasia of the transitional epithelium and then progresses to neoplasia. SCC of the bladder is strongly associated with Schistosoma haematobium, a parasite commonly found in the the Middle East region and especially in Egypt. At first, the adult parasite invades the bladder venous plexus and then the urinary bladder itself. It releases eggs that cause irritation and subsequent chronic granulomatous inflammation in the mucosa and the submucosa.<br/>
'''Educational Objective:''' S. haematobium releases eggs in the bladder that cause irritation and chronic granulomatous inflammation. Eventually, the transitional epithelial wall of the bladder undergoes metaplasia to squamous cell before it finally transforms into neoplasia.<br/>
'''References:''' Rambau PF, Chalya PL, Jackson K. Schistosomiasis and urinary bladder cancer in North Western Tanzania: a retrospective review of 185 patients. Infectious Agents and Cancer. 2013;8:19 +
The patient is presenting with signs and symptoms consistent with theophylline toxicity following theophylline overdose. Theophylline induces the release of catecholamines to stimulate the B-adrenergic receptors. It causes systemic symptoms, such as seizures, vomiting, abdominal pain, marked tachycardia, and electrolyte disturbances, such as those observed in the patient. The final outcome in severe overdose is cardiovascular collapse and death. B-blockers are used as antidotes for the management of theophylline toxicity. Esmolol, a beta-1-selective adrenergic receptor antagonist with an ultrashort duration of action and a short half-life (9 min), is has been used in emergency situations as the B-blocker of choice for theophylline toxicity. Other B-blockers that may be administered in theophylline toxicity include either metoprolol or propranolol.<br/>
'''Educational Objective:''' Esmolol, an ultrashort acting beta-1-selective blocker, is recommended to reverse theophylline toxicity.<br/>
'''References:''' Kempf J, Rusterholtz T, Ber C, et al. Haemodynamic study as guideline for the use of beta blockers in acute theophylline poisoning. Intensive Care Med. 1996; 22:585-587. +
The patient is presenting with acquired C1 esterase inhibitor deficiency, which is a condition that resembles hereditary C1 esterase inhibitor deficiency but involves older age groups. Similar to the hereditary form, acquired C1 esterase inhibitor deficiency manifests with recurrent painless angioedema that involves the head and neck region, with or without respiratory symptoms, that often resolves within 24-48 hours. When patients present with acquired forms of the disease, they must be worked-up extensively for concomitant lymphoproliferative and autoimmune disorders to rule out any secondary etiology for the deficiency, such as a B-cell neoplasm. Similarly, the use of ACE-inhibitors is contraindicated among these patients and medication-induced angioedema must also be ruled out.<br/>
'''Educational Objective:''' C1 esterase inhibitor deficiency may be either acquired or hereditary. Both forms manifest similarly with painless angioedema of the head and neck region. The diagnosis is made by demonstration of low serum C1 esterase inhibitor concentration and when secondary causes (due to medications or systemic disorders) are ruled out.<br/>
'''References:''' Sinclair D, Smith A, Cranfield T, et al. Acquired C1 esterase inhibitor deficiency or serendipity? The chance finding of a paraprotein after an apparently low C1 esterase inhibitor concentration. J Clin Pathol. 2004; 57(4):445-447.<br>
First Aid 2015 page 206 +
Amoebic cysts in a patient with bloody diarrhea and abdominal pain is diagnostic of amoebic dysentery. Amebic dysentery is most common among travelers to developing countries and may be confused with traveler's diarrhea (although it is usually more severe). Intestinal amoebiasis is a parasitic infection, and eosinophilia is one of the classical signs observed among infected patients. Eosinophils play a major role in controlling parasitic infections by producing major basic protein and peroxidase. Eosinophils are induced to grow and to differentiate by specific cytokines, namely interleukin (IL)-5. Other cytokines play different pro-inflammatory roles, such as IL-8 in neutrophil chemotaxis and IL-4 in differentiation into Th2 cells, whereas others have anti-inflammatory roles, such as IL-10 and TGF-beta that are secreted by Treg cells.<br/>
'''Educational Objective:''' IL-5 is activated in parasitic infections to enhance growth and differentiation of eosinophils.<br/>
'''References:''' Takatsu K, Nakajima H. IL-5 and eosinophilia. Curr Opin Immunol. 2008;20(3):288-94.<br>
First Aid 2015 page 207 +
The patient has elevated levels of IgM, which is a pentamer that is produced in the immediate response against pathogens. The shape of IgM is important to allow it to maximally trap antigens. Given the patient's elevated IgM, and deficiency of all other Ig classes, he most likely suffers from hyper IgM syndrome. Hyper IgM syndrome (type 1)is an X-linked disorder caused by a defective CD40L on helper T cells. CD40L (L for Ligand) binds to CD40 on antigen presenting cells, and it's deficiency or mutation prevents immunoglobulin class switching, leading to a deficiency in all classes of immunoglobulin except IgM the primary immunoglobulin produced by B-cells during an antigen response. Four other types of hyper IgM syndrome have bee characterized, all with different modes of inheritance and different mutations involving any of the receptors involved in immunoglobulin class switching. Patients with hyper IgM syndrome classically present with recurrent pyogenic infections (among which Pneumocystis jirovecii pneumonia is very common) due to the inability to mount an appropriate immune response, particularly with the lack of secretory IgA.<br/>
'''Educational Objective:''' IgM is a pentamer. It is increased in hyper IgM syndrome, that is commonly caused by a defective CD40L on helper T cells.<br/>
'''References:''' Image attribution: Artur Jan Fijałkowski<br>
Etzioni A, Ochs HD. The hyper IgM syndrome--an evolving story. Pediatr Res. 2004;56(4):519-25.<br>
First Aid 2015 page 205 +
Lymphatic drainage varies among different structures based on anatomic distance and more importantly based on embryological origins. Since the upper and the lower parts of the anal canal are derived from different embryological origins, their blood supplies and their lymphatic drainage are different despite their anatomic proximity. The pelvic region in general, with the exception of the genitals (testes and ovaries), drains primarily in the superficial inguinal lymph node. These tissues includes the scrotum, the superficial thigh, and the anal canal below the pectinate line.
Conversely, the testes and ovaries have the same unique drainage sites: the superficial and the deep para-aortic plexuses. These sites are usually the first lymph nodes involved in ovarian and testicular cancers.<br/>
'''Educational Objective:''' The anal canal below the pectinate line and the scrotum share the superficial inguinal lymph nodes as the primary lymph node drainage site<br/>
'''References:''' First Aid 2015 page 198 +
Several infectious agents including bacteria, parasites, or virus, undergo different processes to achieve antigenic variation. Salmonella performs a classic example of antigenic variation by the formation of 2 flagellar variants; where filament proteins FLjB and FliC are alternatively expressed. This process is mediated by DNA inversion event at the level of the chromosome. Other organisms and viruses that achieve antigenic variation through entirely different mechanisms, such as pilus protein recombination in Neisseria, or antigenic drifts and shifts in influenza viruses.<br/>
'''Educational Objective:''' Antigenic variation is an important mechanism of immune evasion. Salmonella alternatively expresses 2 flagellar variants to allow antigenic variation.<br/>
'''References:''' Bonifield HR, Hughes KT. Flagellar phase variation in salmonella enterica is mediated by a posttranslational control mechanism. J Bacteriol. 2003;185(12):3567-3574.<br>
Dai Q, Restrepo BI, Porcella SF, et al. Antigenic variation by Borrelia hermsii occurs through recombination between extragenic repetitive elements on linear plasmids. Mol Microbiol. 2006;60(6):1329-43. <br>
First Aid 2015 page 209 +
The patient is presenting with paroxysmal nocturnal hemoglobinuria (PNH). PNH is a disease of the red blood cells (RBC), where deficiency of cell-membrane glycophosphatidylinositol (GPI) causes a subsequent deficiency of GPI-anchored proteins on the RBC surface. The normal physiologic function of the missing GPI-linked proteins is to inhibit complement activation. RBCs without sufficient complement-inhibiting factors are lysed in a complement-dependent fashion. PNH is the only disorder of RBC membrane integrity that is typically acquired (compare to hereditary spherocytosis for example).
Patients typically experience any of the following: Hemolytic anemia, thrombosis, and abnormal hematopoiesis, including pancytopenia. The patient in the vignette describes his nocturnal hemoglobinuria, that is clinically frequently mistaken for hematuria. In PNH, hemoglobin breakdown most commonly occurs in episodes, especially after times of stress, such as exercise or infections. Because thrombosis is a feature of PNH, patients usually have thrombotic events in unusual locations, such as in the hepatic veins or the portal system. In this vignette, the patient was diagnosed with Budd-Chiari syndrome, or hepatic vein thrombosis.
Finally, flow cytometry showing decreased or absent CD55 and CD59 on RBC is diagnostic of PNH. Treatment is usually by eculizumab, a humanized monoclonal antibody that binds to complement protein C5 and inhibits its cleavage into C5a and C5b.<br/>
'''Educational Objective:''' Eculizumab is a humanized monoclonal antibody used to treat PNH.<br/>
'''References:''' Parker C, Bessler M, Richards S, et al. Diagnosis and management of paroxysmal nocturnal hemoglobinuria. Blood. 2005;106(12):3699-3709.<br> +
The patient in this scenario is most likely presenting for clinical manifestations of tuberous sclerosis (TS). In its inherited form, TS is an autosomal dominant disorder, however, the majority of cases are sporadic due to spontaneous mutations in TSC1 or TSC2 genes. TS is characterized by facial angiofibromas, hypopigmented ash leaf spots on the skin, cortical and retinal hamartomas, seizures, mental retardation, renal angiomyolipomas, cardiac rhabdomyomas, and astrocytomas. Not all findings are present in all patients with TS, and symptoms may not manifest very early on in life in some patients. Diagnosis of TS is clinical and does not require genetic confirmation. Most patients require imaging to identify complications of the syndrome. Treatment is symptomatic only with most patients requiring antiepileptics to prevent seizures.<br/>
'''Educational Objective:''' Cardiac rhabdomyomas are associated with tuberous sclerosis.<br/>
'''References:''' Crino PB, Nathanson KL, Henske EP. The tuberous sclerosis complex. N Engl J Med. 2006;355(13):1345-56.
First Aid 2015 page 236 +
Drug-induced lupus erythematosus is a side-effect of long-term use of certain drugs namely procainamide, hydralazine, isoniazid, quinidine, and anti-TNF alpha drugs. Common symptoms closely resemble those of systemic lupus erythematousus and include non-inflammatory arthritis, myalgia, fever and serositis. Drug-induced lupus is usually dose-dependent, taking months to years of exposure to develop. Approximately all (95%) of patients with drug-induced lupus have anti-histone antibodies detected in the serum. A large proportion of patients may also have detectable antibodies but no clinically apparent manifestations. Discontinuation of the drug leads to the resolution of the associated symptoms. This both a diagnostic and therapeutic step in the management of suspected drug-induced lupus.<br/>
'''Educational Objective:''' Drug-induced lupus erythematosus is a side-effect of long-term use of procainamide. Approximately 95% of patients have a positive anti-histone antibody assay.<br/>
'''References:''' Katz U, Zandman-goddard G. Drug-induced lupus: an update. Autoimmun Rev. 2010;10(1):46-50. +