Kidney Disease: Chronic Kidney Disease.

Chronic kidney disease (CKD) affects 37 million US adults. It is characterized by damage to the renal glomeruli, vascular supply, and/or tubulointerstitium through complex processes involving inflammation, fibrosis, and hyperfiltration. CKD typically is asymptomatic but may be detected incidentally via urinalysis showing proteinuria or blood test results showing an elevated creatinine level. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation is the most accurate creatinine-based method for estimating glomerular filtration rate (GFR) in routine practice. Cystatin C level measurement can be considered if patients have factors that might make creatinine-based equations inaccurate (eg, high or low muscle mass). CKD is defined as a GFR less than 60 mL/min/1.73 m2 or persistent evidence of kidney damage on imaging, biopsy, or urinalysis that persists for longer than 3 months. CKD is classified into stages based on estimated GFR, degree of proteinuria, and the cause. Screening guidelines vary. Screening should be considered if patients are at high risk of CKD (eg, patients with diabetes, hypertension, cardiovascular disease, family history of kidney failure). After CKD is identified, is it important to identify and reduce or eliminate exposure to nephrotoxic drugs. Management goals include mitigation of CKD risk factors to slow disease progression, including optimizing management of underlying conditions (eg, hypertension, diabetes).

Kidney Disease: End-Stage Renal Disease.

End-stage renal disease (ESRD) affects approximately 745,000 individuals in the United States. Patients with ESRD are dependent on renal replacement therapy (RRT) via dialysis or kidney transplantation. The two dialysis modalities are peritoneal dialysis and hemodialysis. No differences in long-term mortality rates between the two modalities have been shown. Peritoneal dialysis is performed at home. Hemodialysis typically is performed at a dialysis center through vascular access via an arteriovenous fistula (which must mature for several months before use), an arteriovenous graft (which can be used in as few as 24 hours, depending on the graft material), or a central venous catheter (usable immediately but associated with the highest risk of infection). Transplantation is the treatment of choice for patients with ESRD, and referral should be offered to patients who are candidates. However, some patients with ESRD decide against RRT and opt for supportive care. For these patients, and for patients who choose to discontinue dialysis, palliative care and hospice referral are indicated. For all patients with advanced chronic kidney disease or ESRD, treatment includes management of complications, including hyperkalemia, hypervolemia, metabolic acidosis, anemia, mineral and bone disorders, and protein-calorie malnutrition.

Kidney Disease: Kidney Stones.

Kidney stones have a prevalence of 8.8% in the United States, with men affected more than women (10.6% versus 7.1%). Most stones are composed of calcium oxalate (61%). Calcium phosphate (15%) and uric acid (12%) stones are the second and third most common types. Risk factors include renal and ureteral anatomic abnormalities, family history, previous stones, older age, and various drugs. Factors that increase the risk of stone development include obesity, older age, metabolic syndrome, diabetes, and hypertension. Symptoms include renal colic, dysuria, urinary frequency, hematuria, fever, flank pain, and groin pain. Renal ultrasonography is the recommended first-line imaging modality, and is preferred in pregnant patients. Metabolic testing is recommended in high-risk patients (eg, with a family history of stones, one kidney, malabsorption or intestinal disease). A nonsteroidal anti-inflammatory drug is the first drug of choice for pain management. Medical expulsive therapy (MET) is considered first-line therapy if stones do not resolve with observation. MET is recommended for patients with uncomplicated distal ureteral stones 10 mm in diameter or less. If a stone fails to pass, other interventions (eg, extracorporeal shock wave lithotripsy, percutaneous nephrolithotomy, ureteroscopy, ureteral stents, nephrostomy tubes) can be considered, depending on the situation. Increased fluid intake and dietary interventions can reduce the risk of recurrence.

Stable Coronary Artery Disease: Treatment.

Stable coronary artery disease refers to a reversible supply/demand mismatch related to ischemia, a history of myocardial infarction, or the presence of plaque documented by catheterization or computed tomography angiography. Patients are considered stable if they are asymptomatic or their symptoms are controlled by medications or revascularization. Treatment involves risk factor management, antiplatelet therapy, and antianginal medications. Tobacco cessation, exercise, and weight loss are the most important lifestyle modifications. Treatment of comorbidities such as diabetes mellitus, hyperlipidemia, and hypertension should be optimized to reduce cardiovascular risk. All patients should be started on a statin unless contraindicated. No data support the routine use of monotherapy with nonstatin drugs such as bile acid sequestrants, niacin, ezetimibe, or fibrates. Studies of niacin and fibrates as adjunctive therapy found no improvement in patient outcomes. Aspirin is the mainstay of antiplatelet therapy; clopidogrel is an alternative. Antianginal medications should be added in a stepwise approach beginning with a beta blocker. Calcium channel blockers, nitrates, and ranolazine are used as adjunctive or second-line therapy when beta blockers are ineffective or contraindicated. Select patients may benefit from coronary revascularization with percutaneous coronary intervention or coronary artery bypass grafting.

Electrolytes: Sodium Disorders.

Sodium disorders (ie, hyponatremia, hypernatremia) are common electrolyte disturbances in clinical medicine and are associated with increased rates of morbidity and mortality. Etiologies of hyponatremia are classified into four categories. The first is pseudohyponatremia, in which the sodium level is low due to hyperproteinemia, hyperlipidemia, or hyperglycemia. The other three categories are based on overall patient fluid status and include hypovolemic (commonly due to fluid loss), hypervolemic (commonly due to fluid retention from heart failure, cirrhosis, or renal failure), and euvolemic (most often because of syndrome of inappropriate secretion of antidiuretic hormone). Hypovolemic hyponatremia is managed by rehydration with isotonic saline. Hypervolemic hyponatremia is managed by addressing the underlying cause. Euvolemic hyponatremia is managed by restricting free water intake, addressing the underlying cause, and occasionally with drugs (eg, vasopressin receptor antagonists). Patients with severe or acutely symptomatic hyponatremia (eg, altered mental status, seizures), including those with acute symptomatic exercise-induced hyponatremia, require urgent treatment. This should consist of hypertonic saline administration along with monitoring of sodium levels to avoid overly rapid correction. Hypernatremia most often occurs because of water loss or inadequate water intake. Depending on severity, management involves oral or intravenous hypotonic fluids and addressing the underlying cause.

Diagnosis and Management of Endometrial Cancer.

Endometrial cancer is the most common gynecologic malignancy. It is the fourth most common cancer in women in the United States after breast, lung, and colorectal cancers. Risk factors are related to excessive unopposed exposure of the endometrium to estrogen, including unopposed estrogen therapy, early menarche, late menopause, tamoxifen therapy, nulliparity, infertility or failure to ovulate, and polycystic ovary syndrome. Additional risk factors are increasing age, obesity, hypertension, diabetes mellitus, and hereditary nonpolyposis colorectal cancer. The most common presentation for endometrial cancer is postmenopausal bleeding. The American Cancer Society recommends that all women older than 65 years be informed of the risks and symptoms of endometrial cancer and advised to seek evaluation if symptoms occur. There is no evidence to support endometrial cancer screening in asymptomatic women. Evaluation of a patient with suspected disease should include a pregnancy test in women of childbearing age, complete blood count, and prothrombin time and partial thromboplastin time if bleeding is heavy. Most guidelines recommend either transvaginal ultrasonography or endometrial biopsy as the initial study. The mainstay of treatment for endometrial cancer is total hysterectomy with bilateral salpingo-oophorectomy. Radiation and chemotherapy can also play a role in treatment. Low- to medium-risk endometrial hyperplasia can be treated with nonsurgical options. Survival is generally defined by the stage of the disease and histology, with most patients at stage I and II having a favorable prognosis. Controlling risk factors such as obesity, diabetes, and hypertension could play a role in the prevention of endometrial cancer.

Diagnosis and management of sodium disorders: hyponatremia and hypernatremia.

Hyponatremia and hypernatremia are common findings in the inpatient and outpatient settings. Sodium disorders are associated with an increased risk of morbidity and mortality. Plasma osmolality plays a critical role in the pathophysiology and treatment of sodium disorders. Hyponatremia and hypernatremia are classified based on volume status (hypovolemia, euvolemia, and hypervolemia). Sodium disorders are diagnosed by findings from the history, physical examination, laboratory studies, and evaluation of volume status. Treatment is based on symptoms and underlying causes. In general, hyponatremia is treated with fluid restriction (in the setting of euvolemia), isotonic saline (in hypovolemia), and diuresis (in hypervolemia). A combination of these therapies may be needed based on the presentation. Hypertonic saline is used to treat severe symptomatic hyponatremia. Medications such as vaptans may have a role in the treatment of euvolemic and hypervolemic hyponatremia. The treatment of hypernatremia involves correcting the underlying cause and correcting the free water deficit.

Suspected hypercalcemia induced ST-segment elevation in a patient with sarcoidosis.

Sarcoidosis is a multisystem granulomatous disease that affects 10 to 20 people per 100,000 in the United States. Hypercalcemia is a known side effect of the disease and in rare instances has been shown to cause ST-segment elevation on electrocardiogram testing that mimics myocardial infarction. Herein, we present a rare case of a 55-year-old, asymptomatic African-American male with sarcoidosis and hydrochlorothiazide usage presenting with ST-segment elevation of the anterior leads secondary to hypercalcemia. Urgent cardiac catheterization showed normal coronary arteries without blockage. The patient's hypercalcemia was corrected with intravenous fluids and the ST-segment elevation resolved. The exact mechanism of ST-segment elevation induced hypercalcemia is unknown. Treatment of the underlying cause of the hypercalcemia is the mainstay of therapy.

A case report of acute idiopathic scrotal edema.

Acute Idiopathic Scrotal Edema (AISE) is an uncommon cause of bilateral scrotal swelling encountered in primary care. AISE is usually seen in children; however, several case reports have shown that AISE can occur in adult males. We present an active duty adult male who presented with AISE while deployed in Afghanistan. The clinical course of AISE is usually benign with labs and ultrasound being unremarkable. Besides swelling, the most common symptom tends to be intense scrotal puritis. Treatment for AISE is watchful waiting and conservative therapy. Full symptom resolution usually occurs within 24 hours.

Thrombocytopenia.

Thrombocytopenia is defined as a platelet count of less than 150 × 10(3) per µL. It is often discovered incidentally when obtaining a complete blood count during an office visit. The etiology usually is not obvious, and additional investigation is required. Patients with platelet counts greater than 50 × 10(3) per µL rarely have symptoms. A platelet count from 30 to 50 × 10(3) per µL rarely manifests as purpura. A count from 10 to 30 × 10(3) per µL may cause bleeding with minimal trauma. A platelet count less than 5 × 10(3) per µL may cause spontaneous bleeding and constitutes a hematologic emergency. Patients who present with thrombocytopenia as part of a multisystem disorder usually are ill and require urgent evaluation and treatment. These patients most likely have an acute infection, heparin-induced thrombocytopenia, liver disease, thrombotic thrombocytopenic purpura/hemolytic uremic syndrome, disseminated intravascular coagulation, or a hematologic disorder. During pregnancy, preeclampsia and the HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome are associated with thrombocytopenia. Patients with isolated thrombocytopenia commonly have drug-induced thrombocytopenia, immune thrombocytopenic purpura, pseudothrombocytopenia, or if pregnant, gestational thrombocytopenia. A history, physical examination, and laboratory studies can differentiate patients who require immediate intervention from those who can be treated in the outpatient setting. Treatment is based on the etiology and, in some cases, treating the secondary cause results in normalization of platelet counts. Consultation with a hematologist should be considered if patients require hospitalization, if there is evidence of systemic disease, or if thrombocytopenia worsens despite initial treatment.