By Y. Faesul. Houston Baptist University. 2018.

This is due to difficulties in membrane protein purification discount 100 mg danazol overnight delivery breast cancer walk nyc, expression generic 100mg danazol fast delivery recent women's health issues, and crystallization (Caffrey, 2003), which is still in its childhood. To date, only about 2% (1462 by Sept 2011) of the structures are from transmembrane proteins (75594 structures in total). Out of these there are only 302 unique structures (proteins of same type but from different species are included) (Irvine). Moreover, a significant number of the membrane protein structures determined are at relatively low resolutions (Lindahl & Sansom, 2008). However, there are tremendous efforts as to ameliorate the methods in order to obtain atomic resolution structures of membrane protein molecules (Newby et al. Thus, for Molecular Modeling and Simulation of Membrane Transport Proteins 375 the past two decades, the number of available structures of membrane proteins has been climbing the exponential foot of the growth curve, since it is doubling every three years (Theobald & Miller, 2010). For a medicinal chemist, the availability of a growing number of structures, paves the way for further in silico studies. Some are very promising in a way that they can be used as templates in order to build up a homology model of the membrane protein of interest. Due to significant increase in computational power and improvements in parallelization techniques, nowadays simulations of membrane transport proteins may stretch up to microseconds - that is, to physiologically relevant time scales. Fortunately, Mother Nature was not too generous in providing unique structural folds for functionally related proteins, as the structural arrangement within a family of homologous proteins is much higher conserved than the respective amino acid sequences (Lesk & Chothia, 1980). Thus, in many cases the combination of a primary sequence on the one hand and one or more reasonably well-resolved homologue structures on the other hand can result in homology models surprisingly well representing the molecular reality, paving the way to successful comparative modeling studies. The process of predicting the 3D structure of a protein can be achieved by four main steps: fold assignment, target-template sequence alignment, building and evaluation of the models (Cavasotto, 2011). Although generally a high percentage of global sequence identity is a good indicator for the model quality to be expected, it must be kept in mind that the identity in the area of interest, i. One should strive to put the main focus during template selection on facilitating a maximum of accuracy in modeling those vital regions. As mentioned earlier, it offers the coordinates of structurally resolved proteins, including large amounts of surplus information like primary sequence, experimental settings or co- bound ligands and ions. Conserved residues and regions of experimentally determined proximity need to be aligned as accurately as possible. Multiple alignments of sequences belonging to the same gene family can significantly enhance the performance of the search for conserved residues or even regions, but thorough literature search and manual adjustment of the alignment are inevitable in order to achieve best results. It turned out, that advanced modeling tools and human intervention contributed about equally to the success of the individual approaches. Although automated homology modeling methods exist, the yielded models tend to lack accuracy, especially in cases of low sequence identity (Dalton & Jackson, 2007). Conserved secondary structural elements like α- helices or β-sheets are inherited, being responsible for the general shape of the model. Several homology modeling approaches also try to include information about known ligands into the binding site construction in order to meet its particular geometry (Evers & Klebe, 2004; Sherman et al. Subsequently, assignment of the side chain conformations needs to be done according to steric and energetic constraints. Identical residues usually can be considered to be oriented similarly, likewise highly similar amino acids. For non related residues, rotamer libraries can provide initial geometrical guesses (Schrauber et al. Up to 30% of side chain conformations in X-ray structures do not correspond to usual rotamers, yet adopting energetically allowed conformations. Naturally, selecting the most probable side chain orientation solely according to statistical criteria is problematic, so methods including structural features of the local environment have been developed (Deane & Blundell, 2001). Still, some cases require manual adjustment, for instance the incorporation of known disulfide bridges, specific internal hydrogen bonds or ion binding pockets. Especially flexible loop regions lacking a structural template are difficult to predict, since the calculation time increases nearly exponentially with the degrees of Molecular Modeling and Simulation of Membrane Transport Proteins 377 freedom added by every flexible residue. Knowledge-based strategies try to find structural guesses by automated database search for related sequence sections in other proteins, possibly not even close to being genetically similar.

After graduation buy 100mg danazol with amex pregnancy hip pain, several interesting topics are offered for PhD training purchase 50 mg danazol free shipping menstruation 19th century, which lasts for three years. If interested, outstanding graduates of the English General Medicine and Dentistry programs may join these PhD courses (“English PhD-program”). Special education for general practitioners has been recently started and a new system is in preparation now for the training of licensed physicians in Debrecen. The accredited PhD programs include the following topics: -Molecular and Cell Biology; Mechanisms of Signal Transduction -Microbiology and Pharmacology -Biophysics -Physiology-Neurobiology -Experimental and Clinical Investigations in Hematology and Hemostasis -Epidemiological and Clinical Epidemiological Studies -Cellular- and Molecular Biology: Study of the Activity of Cells and Tissues under Healthy and Pathological Conditions -Immunology -Experimental and Clinical Oncology -Public Health -Preventive Medicine -Dental Research The PhD-programs are led by more than 100 accredited, highly qualified coordinators and tutors. Medical Activity at the Faculty of Medicine The Faculty of Medicine is not only the second largest medical school in Hungary, but it is also one of the largest Hungarian hospitals, consisting of 49 departments; including 18 different clinical departments with more than 1,800 beds. It is not only the best-equipped institution in the area but it also represents the most important health care facility for the day-to-day medical care in its region. The Kenézy Gyula County Hospital (with some 1,400 beds) is strongly affiliated with the University of Debrecen and plays an important role in teaching the practical aspects of medicine. There are also close contacts between the University and other health care institutions, mainly (but not exclusively) in its closer region. The University of Debrecen has a Teaching Hospital Network consisting of 24 hospitals in Israel, Japan and South Korea. Scientific Research at the Faculty of Medicine Scientific research is performed both at the departments for basic sciences and at the laboratories of clinical departments. The faculty members publish about 600 scientific papers every year in international scientific journals. According to the scientometric data, the Faculty is among the 4 best of the more than 80 Hungarian research institutions and universities. Lots of scientists reach international recognition, exploiting the possibilities provided by local, national and international collaborations. Internationally acknowledged research areas are Biophysics, Biochemistry, Cell Biology, Immunology, Experimental and Clinical Oncology, Hematology, Neurobiology, Molecular Biology, Neurology, and Physiology. Dermatological Allergology Full Professor, Head of Division of Human István Juhász M. Clinical And Health Psychology Associate Professor, Head of Division of Attila Bánfalvi M. The requirements in these premedical science subjects are rigorous, thus it is recommended that students who need a period of preparation prior to beginning the General Medicine, Dentistry or Pharmacy Program join the Basic Medicine Course. Students successfully completing the course are directly admitted to their chosen program. Students are encouraged to ask questions related to the topic of the lectures discussed, and participate in solving problems related to the topic of the seminar. Some professors will ask for students to volunteer information, but some professors call on students randomly. It is, thus, a good idea to come to class prepared so as not to be embarrassed in front of the class. The usage of electronic devices, textbooks and any form of interaction between students during the tests is strictly forbidden. Violation of these above mentioned regulations results in an immediate and unconditional dismissal from the program. Attending lectures is strongly recommended, attendance of seminars is compulsory and recorded. Absence can significantly affect your understanding and can have serious implications of progression in your studies. One might have a maximum of three seminar absences per semester to have the opportunity to get exemption. Missed seminars cannot be made up, unless one obtains prior permission to be absent. Self Control Tests, End of Semester Exams, and Final Exams will be assessed as follows. Self Control Test nd th 2 week: 6 week: Lecture: Proteins, carbohydrates and lipids 3.

Care must be taken not r Dehydration is exacerbated by vomiting cheap danazol 100 mg without a prescription breast cancer 4 cm, which is due to change the osmolality too rapidly danazol 50 mg line women's health center waldorf, as this can lead to to central effects of ketosis. For this reason, normal saline is always Clinical features used initially: Nausea, vomiting, abdominal pain, hyperventilation, r 1st hour 1. Replacement should be faster if Shock and acute renal failure, cerebral oedema may oc- patients are shocked and slower if there are signs of cur during rehydration, adult respiratory distress syn- cardiac failure, fluid overload or cerebral oedema. Supplementa- tion is always needed, because potassium follows glu- Investigations cose into the cells. However, there is a danger of hyper- The diagnosis requires the demonstration of diabetes, kalaemia, causing cardiac arrhythmias, so if K+ levels are ketosis and a metabolic acidosis. An arterial blood gas sample Insulin: Soluble insulin is administered intravenously by is also required to demonstrate and assess the severity of an infusion pump – start with 10 units per hour and metabolic acidosis. Serum amylase greater than three- cutaneous or intramuscular insulin can reverse the ke- fold normal is suggestive of acute pancreatitis, which toacidosis. It therefore should not normally be used in the is rehydration and correction of electrolyte imbalances. Chapter 11: Diabetes mellitus 461 Prognosis are absent (hyperventilation, ketotic breath) but confu- Overall mortality is ∼10% and as high as 50% in older sion, drowsiness and coma are more common. It is the most common cause of death in diabetic patients under 20 Complications years old. Thromboembolic disease, such as stroke, mesenteric arterythrombosis,deepveinthrombosisandpulmonary embolism. Precipitating factors include infection, myocardial in- farction and stroke, or diabetogenic drugs such as glu- Management cocorticoids and thiazide diuretics. Patients require emergency fluid resuscitation with nor- mal saline and potassium replacement (as for diabetic Pathophysiology ketoacidosis). Prophylactic low-dose heparin to prevent nesis, uncontrolled ketogenesis does not occur. Any underlying cause is insufficient insulin to prevent increased glucose pro- should be identified and treated. This compounds the hyperos- molarity caused by the hyperglycaemia, which increases Hypoglycaemia blood viscosity, predisposing to thromboembolic disor- Definition ders. If untreated, it leads to confusion and eventually Lowserumglucosecausedbyinsufficienthepaticglucose coma. Clinical features Aetiology Often occurs in elderly undiagnosed patients, who Insulin overdose (accidental or deliberate self harm), present with polyuria, intense thirst, weight loss and sulphonylurea overdose, malnutrition, fasting, exercise blurred vision. Alcohol impairs gluconeogenesis 462 Chapter 11: Endocrine system and can cause hypoglycaemia in diabetic patients. Other tests causes include insulinomas (see page 222) and Addison’s may be required to identify the underlying cause. Management Clinical features This is a medical emergency and requires immediate Patients become irritable, pale, weak and sweaty. Untreated the condition progresses to con- followed by a more complex carbohydrate to prevent fusion, seizures and coma. The diagnosis can be confirmed on bedside blood sugar r Further management depends on severity and the un- testing, a formal laboratory glucose sample should be derlying cause. Hypersplenism occurs when the spleen is func- Lymphadenopathy tionally overactive and can result from any cause of splenomegaly. The usual function of lymph nodes is to allow anti- gen recognition, proliferation and affinity maturation of mature lymphocytes. They usually become enlarged Bleeding tendency when active/reactive because of infection. Enlargement of lymph nodes can be localised or generalised (see Ta- Characterisation of a bleeding tendency requires multi- ble 12. Localised lymphadenopathy r Generalised haemostatic defects are suggested by Infection, e. It occurs in severe infections, tuber- blood vessels platelets and coagulation: culosis or malignant infiltration of the bone marrow.

Countries in Africa with Egypt Communities practicing female circumcision Mauritania Mali Senegal Niger Chad Sudan Eritrea Burquina Djbouti Gambia Guinea- Faso Nigeria Bissau C cheap danazol 50 mg otc womens health 33511. Ethiopia Sierra Leone Cameroon Liberia Somalia Ghana Benin Democratic Uganda Cote Togo Republic Kenya d’Ivoire of Congo (Ivory Coast) (Zaire) Tanzania Figure 4 buy 200 mg danazol otc menstruation 2 weeks apart. The presence of this scar tissue, which is less elastic than the perineal and vaginal tissue would normally be, might cause differing degrees of obstruction and tears or episiotomy. In the opposite, Abdulrahim3 work shows that, with proper management, there is no sta- tistically significant difference in outcome of labour between women who deliver vagina- lly, with and without defibulation. It is sufficient to reassure the patient that she and her baby are under no special risk. Under no circumstance should a woman be subjected to caesarean section solely to avoid defibulation, regardless of whether she requests it or the provider suggests it6. For some authors the optimum time for a defibulation is the second trimester under local or spinal anaesthesia. This is thought to prevent acute problems at the time of delivery related to the risk of un- familiarity of the staff on duty with defibulation. Other professionals and a number of women prefer de-infibulation during labour as part of the birth process as they then only have to experience a painful procedure once. Care must be taken not to injure intact parts of the clitoris that may be buried under the anterior part of the hood. The edges of the skin are stitched apart with a running absorbable, non reactive suture. Any extension of the an- terior incision above the urethra may be repaired at this time. A routine repair of the episiotomy or perineal tear is also frequently required post labour. Careful cut of the scar between two fingers to avoid injuring urethra or intact parts of the clitoris. Delivery of the baby, suture edges of the skin above the urethra and reparation of the episiotomy. Although defibulation has been shown to be safe and effective, health care professionals cannot fail to be concerned about the overall problems associated with female genital mu- tilation. There is a continuing need for health education which stresses the risks and com- plications of female genital mutilation, while explaining that the origin is more of tradition than of religion. However in the Muslim world, such a change of attitude towards the pro- cedure has to come from within and cannot be successfully imposed from outside. In conclusion, although the surgical technique of intrapartum defibulation is simple and safe, this should not undermine the continuing efforts towards abandoning female genital mutilation altogether7. The long-term reproductive health con- sequences of female genital cutting in rural Gambia: a community-based survey. Pain has no advantages and besides the negative psychological impact on the mother, it can produce low placental perfusion by different ways that at the end can cause fetal hypoxia. Nowadays, women demand pain release, and some of them even consider this fact as a right. With all the respect to women who desire a «natural labour», just the desire of a woman to have pain release in absence of contraindications should be enough to guaran- tee obstetric analgesia. By anaesthesia we assume the lack of sensations, mainly painful ones, associated to lack of conscience, and this can be achieved with general anaesthetics drugs. Analgesia is the lack of pain sensation, and this has no effect on conscientious; this is what is desirable in obstetrics and what is achieved with loco-regional analgesia. Fifteen trials involving 12,791 women met inclusion criteria and provided usable outcome data. Moreover it is easy to apply, cheap, without known risks besides the transient local pain. Its main indication is the relief of low back pain in early labour, women with no desire of epidural analgesia o contraindication for it.

Definition r Finasteride is a 5 alpha reductase inhibitor which in- Urinary incontinence is the involuntary loss of urine hibits the conversion of testosterone to dihydrotestos- from the urethra buy danazol 50 mg overnight delivery women's health birth control options. It is also useful order danazol 200 mg with mastercard menstruation fatigue, but generally less effective for and functional impact on the individual. This is mainly due to detrusor instability/over- 30% of women <65 years but only up to 5% of men <65 activity. Rates are much higher in certain settings such as care of r Overflow incontinence is continual or unprecipitated the elderly institutions (up to 45%) and psychiatric care leakage without urge. Bladder outflow obstruction may lead Age to overflow incontinence due to bladder decompen- Increases with age. Rare causes include spinal cord compression affecting the sacral segments (S2, 3 and 4) or the conus medullaris. F > M Acomprehensive examination is important and can avoid the need for specialist tests. It is important to as- Aetiology sess fluid balance, mobility, cognitive ability and relevant Incontinence has been associated with many conditions neurology. Rectal examination for constipation, rectal and risk factors such as chronic cough, depression, de- masses and vaginal speculum examination for atrophy, mentia, pregnancy, vaginal delivery (particularly with masses, cystocele or rectocele. Toremaincontinentthere r Avoiding diary is useful to record the time, volume must be: and relevant events, e. This is due to poor sphincter func- Stress incontinence: Initially non-surgical options tion. This r Pelvic floor (Kegel) exercises (with or without weigh- may be precipitated by the sound of running water, tedcones) may be used but are dependent on the Chapter 6: Urinary tract infections 265 motivation of the patient. Systemic or topical oestro- r Inspinalcordcompressionemergencydecompression gen therapy may be of benefit. Ring tions intermittent self-catheterisation is the preferred pessaries are useful for those with uterine prolapse. For vaginal cys- Urinary tract infections toceles (where the bladder herniates into the vaginal canal), a transvaginal approach may be used to re- pair the cystocele but this is generally less effective. In females, vaginitis is another syndrome Urge incontinence: unlike stress incontinence, be- which commonly overlaps. Surgery (clam cystoplasty to increase the size of the blad- Age der using bowel) is rarely successful. In patients with cognitive awareness of bladder Sex filling and the ability to independently toilet, bladder F > M training is used to learn methods of deliberately sup- pressing the urge to pass urine. In patients without cognitive awareness or lack of motivation to remain Aetiology dry, scheduled or prompted voiding reduces the num- Most frequently due to bacteria, in particular E. These and Histoplasma capsulatum), parasites (the protozoan tend to cause a dry mouth and may cause constipa- Trichomonas vaginalis and the fluke Schistosoma haema- tion and/or urinary retention. Pathophysiology Combined stress and urge incontinence may be treated r Bacterialvirulencefactors:Criticaltothepathogenesis with behavioural therapy with or without medical ther- of bacteria is adherence to the uroepithelium as infec- apy. Surgicaltreatmentappearstobelesseffectivethanin tions ascend from the urethral orifice to the bladder pure stress incontinence. Proteus), duction of urease, causes the alkalinisation of urine, so it hydrolyses urea and increases ammonia, which fa- that phosphate, carbonate and magnesium are more cilitates bacterial adherence. Other important risk factors include sexual intercourse, diabetes melli- Investigations tus, immunosuppression, instrumentation (including Mid-stream urine for urinalysis (dipstick testing), mi- catheterisation) and pregnancy. A culture is regarded as Urine itself is inhibitory to the growth of normal uri- 5 positive if >10 of a single organism per mL. Further investigations are required in children Clinical features (see page 268), males and females with recurrent infect- Acute cystitis typically presents with dysuria (a burning ions. Macroscopic haematuria is not uncommon, although this should Management prompt further investigation for any other underlying Empirical antibiotic therapy is used in symptomatic pa- disease such as urinary stones or a bladder malignancy. Pyelonephritis may present with few lower urinary tract Uncomplicated cystitis in a woman usually only requires symptoms, but more commonly causes systemic upset 3daysoforal antibiotics, whereas longer courses are re- withfever,rigors,chills,andloinpainortenderness. Both Intravenous antibiotics should be used in those who are pyelonephritis and prostatitis may be due to ascending systemically unwell or those who are vomiting. Quinolones such present nonspecifically with fever, falls, vomiting, or as ciprofloxacin are useful as resistant E. Macroscopy r Intravenoustherapyisoftenwithacephalosporinwith The urine is cloudy due to the pyuria (pus cells) and or without gentamicin. Over time, recurrences can cause chronic sistance, and some centres advise a ‘cycling regime’, e.

Definition Typhoid (Salmonella typhi) and paratyphoid (Salmon- Botulism ella paratyphi A generic danazol 100mg without prescription menstrual bloating treatment, B or C)produce a clinically identical disease buy danazol 200mg fast delivery menstruation meaning. Definition Botulism is a serious food poisoning caused by the Gram Aetiology/pathophysiology positive bacillus Clostridium botulinum. Organisms pass The bacteria are soil borne, spores are heat resistant to via the ileum and the lymphatic system to the systemic 100˚C. Some secrete salmonella for over a 1 Food borne botulism in which toxin in the food is year and measurement of Vi agglutinin is used to detect ingested. Clinical features 3 Wound botulism in which the organism is implanted 1 The condition typically runs a course of around 1 into a wound. There is gradual onset of a viral like illness with headache Pathophysiology and fever worsening over 3–4 days. There is initially Toxins are transported via the blood stream to the pe- constipation. Botulinum toxin acts to block 2 Week 2 the patient appears toxic with dehydration, neurotransmission. Patients develop an erythematous maculopapular-blanching Clinical features rash with splenomegaly. The illness starts with nausea and vomiting 12–72 hours 3 During week 3 complications include pneumonia, afteringestingtheorganism. Neurologicalfeaturesresult haemolytic anaemia, meningitis, peripheral neuropa- from neuromuscular blockade: blurred vision, squint thy, acute cholecystitis, osteomyelitis, intestinal perfo- due to lateral rectus muscle weakness, the pupil is fixed ration and haemorrhage. Laryngeal 4 Over the subsequent week there is a gradual return to and pharyngeal paralysis heralds the onset of a gener- normal health. Chapter 4: Gastrointestinal infections 153 Investigations The toxin is demonstrable in the faeces. Intravenous antitoxin and guanidine hydrochlo- ride to reverse neuromuscular blockade has been used. The serovar 0:1 is the major pathogenic strain and Clinical features is divided into two biotypes; classical and the more Theincubationperiodisbetweenafewhoursand1week. Phage typing can be used to but in severe cases there may be watery diarrhoea with examine epidemics to try and see if the observed condi- mucous, termed rice water stool. Serotyping of Biotype: growth on Bacteria somatic O media, and enzyme antigens production Classical Serovar 0:1 Vibrio cholera El Tor Non 0:1 Figure 4. Caseating granulomas and fibrosis may volaemia may be made using clinical indices such as the result in stricture formation and obstructions. Clinical features r In significant volume depletion intravenous saline The presentation depends on the site of infection and should be administered. Patients may present with put should be documented hourly and reviewed with diarrhoea, abdominal pain, alteration of bowel habit, care. Gastric outflow obstruction may result in choice using a solution containing sodium, potas- vomiting and a succussion splash on examination. Clinically gastroin- glucose to facilitate absorption, rice-based polymers testinal tuberculosis may be difficult to distinguish from have been used in place of glucose with some evi- Crohn’s disease. Investigations r Tetracycline or ciprofloxacin can be used to shorten Abdominal ultrasound may demonstrate mesenteric duration and reduce severity of illness. Management Aetiology/pathophysiology Treatment with a combination of rifampicin, isoniazid, Infections are most common in the immunosuppressed pyrazinamideandethambutolifresistanceislikely. Sources of gastroin- apy should continue for 1 year in gut infections and testinal tuberculous infections: 2years in peritonitis. Intestinal tuberculosis occurs at any point of turbulence, Disorders of the abdominal wall e. Glucose, anhydrous 75 Potassium 20 Incidence Citrate 10 85% occur in males, with a lifetime risk of 1 in 4 males, Total Osmolarity 245 but less than 1 in 20 females. Chapter 4: Disorders of the abdominal wall 155 toneum dragged down into the testes during the embryonic descent of the testes from the posterior Skin abdominal wall. It is usually obliterated leaving the tunica vaginalis as a covering of the testes. Femoral hernias are particularly prone to incarceration or strangulation, Figure 4. Females have femoral hernias more often than Aetiology/pathophysiology males, but inguinal hernias are still the most common Congenital hernias exploit natural openings and weak- hernia in females (by 4 to 1). They may not become obvious until later in life and may be predisposed to by coughing straining, surgical incisions and muscle splitting.

Antibiotic therapy may be indicated when symptoms do not resolve with sup- portive care and stool-reducing agents 50mg danazol with visa women's health big book of yoga ebook. For travelers returning from the non-coastal regions of Mexico discount danazol 100mg without prescription menopause 34 symptoms, double-strength trimethoprin-sulfamethoxazole twice a day is recommended. For other patients, ciprofloxacin (750 mg), levofloxacin (500 mg), norfloxacin (800 mg), or azithromycin (1000 mg) are recommended. For immune compromised patients and elderly patients with comorbidities, prophylaxis with trimethoprim-sulfamethoxazole or a fluoroquinolone can be prescribed. If the etiology is still unclear and the patient is not improving while off oral intake, hospital admission and consultation with a gastroenterologist may be indicated. Diseases such as inflammatory bowel disease or ischemic bowel disease must be considered. Treatm ent Fluid and electrolyte replacement are fundamental to the treatment of acute diarrhea. For those with more serious volume deficits, or elderly patients or infants, hospitalization and intravenous hydration may be necessary. Bismuth subsalicylate may be used to alleviate the gastrointestinal symptoms, but should not be used in an immune-compromised individual because of the risk of bismuth encephalopathy. Many physicians choose to treat patients with moderately ill or severely ill appear- ance empirically with ciprofloxacin 500 mg twice daily for 5 days. Travel er’s Prophylaxis The best method in preventing traveler’s diarrhea, which is principally caused by enterotoxigenic E coli, is avoidance of food and water in areas of high risk. Travelers should be advised to drink only bottled water, and avoid eating foods from street vendors or unhygienic locations. Medical prophylaxis (either bismuth subsalicylate or antibiotic) should not be used for longer than 3 weeks. Rotavirus usually causes a watery diarrhea, and is especially common in the winter. S aureus usually causes prominent vomiting and diarrhea within a few hours of food ingestion as a consequence of the toxin produced. Raw seafood may harbor Vibrio spec; thus, the history of eating raw oysters makes Vibrio-related infection likely. One should be cautious when assessing acute diarrhea in immunosup- pressed patients, very young, or elderly patients. Significant dehydration, grossly bloody diarrhea, high fever, and nonre- sponse after 48 hours are warning signs of possible complicated diarrhea. In general, acute uncomplicated diarrhea can be treated with oral electrolyte-fluid solution with or without empiric ciprofloxacin. Patient states he was sleeping comfortably but the sudden onset of severe, constant pain that radiates from his back to his abdomen and down toward his scrotum caused him to awaken. He admits to having had occasional hematuria but denies ever having this type of pain before. His blood pressure is 128/76 mm Hg, heart rate is 90 beats per minute, temperature is 37. Abdominal examination demonstrates good bowel sounds, and no abdominal distension and costovertebral angle tenderness. He appears to be in moderate distress and has not previously experienced these symptoms. Strain all urine once the diagnosis of nephrolithiasis is suspected and perform stone analysis on any stone passed. Learn to order the appropriate laboratory and radiographic studies to diagnose nephrolithiasis. Considerations This patient has a very typical presentation for nephrolithiasis; male (three times more common in men than in women) and the history of the sudden onset of pain that radiates from his back toward his abdomen. The emergency department physi- cian must be careful to rule out other acute abdominal etiologies that may mimic the same presentation (Table 22–1 lists the differential diagnosis). Patients with neph- rolithiasis often have difficulty in finding a comfortable position. Patients with an acute abdomen often feel better when they remain supine without moving or with their knees bent toward their chest. A history of dark-brown-tinged urine may represent old blood in the urine (ie, from a stone high in the calyx), while a complaint of bright red blood in the urine may be more consistent with a lower urinary tract stone.