Hypokalemia - Differential Diagnosis Algorithm
Extra-renal Losses:
• Normal Acid-Base: Low intake
• Metabolic acidosis: Gl tract loss (Diarrhea)
Renal Losses:
• Metabolic acidosis: Proximal and distal RTA, Ureterosigmoidoscopy
• HTN, Low Aldosterone: Liddle's Syndrome, Licorice, Carbenoxolone, SAME, Cushing Syndrome
• HTN, High Aldosterone: Malignant HTN, Renovascular HTN, Renin secreting tumor, Primary hyperaldosteronism
• HTN Absent: Loop and thiazide diuretics, Bartter syndrome, Gitelman syndrom, Vomiting, Non-reabsorbable anions
Dr Priti Meena @priti899
#Hypokalemia #Differential #Diagnosis #Algorithm #causes #potassium #low #nephrology
Salicylate Toxicity - Diagnosis and Management
Consider if:
1) Patient is hot and altered
2) You see tachypnea with no respiratory cause
3) Labs show anion-gap metabolic acidosis
4) Presentation seems like DKA, sepsis, PNA, meningitis
5) History of acute or chronic ingestion/exposure
Symptoms: Nausea, Vomiting, Tinnitus, Hearing loss, Dizziness, Altered, Seizure, Coma
Exam: Tachypnea, Tachycardia, Elevated temp, Diaphoresis, Pulmonary edema, Shock
Labs: Anion-Gap Metabolic Acidosis, Respiratory Alkalosis, High Lactate, Low Potassium, Low Glucose, Salicylate level
- Toxic Salicylate Level: 150mg/kg
Management:
1) Resuscitation
2) Urine pH > 7.5 with Alkalinzation
3) Glucose > 4.5 mmol/L
4) K > 4.5 mmol/L
5) Dialysis
By Sarah Foohey @SarahFoohey
#Salicylate #Aspirin #Toxicity #Toxicology #diagnosis #management #Treatment
Bleeding manifestations
Petechiae are small, flat, red, discrete areas of skin bleeding that are typically <2 mm in diameter. They are non-blanching, nonpalpable, and occur in dependent areas of the body Purpura results from coalesced petechiae. Purpura due to vasculitis is usually palpable and may be pruritic, and the distribution does not follow dependent areas. Wet purpura is the most predictive of serious bleeding in individuals with thrombocytopenia. Bruise (also called ecchymosis) is caused by the subcutaneous accumulation of extravasated blood. The skin is flat, and the color evolves over time from purplish blue to reddish brown to greenish-yellow, reflecting the metabolism (breakdown) of hemoglobin to biliverdin and bilirubin. Hematoma is a collection of blood in the extravascular space. Hematomas and hemarthroses (joint bleeding) are typical of coagulation factor deficiencies.
Von Willebrand factor
Glycoprotein
Synthesized in endothelial cells & megakaryocytes.
Excessive bruising & prolonged bleeding
Levels vary with stress; increase with estrogens, vasopressin, GH & adrenergic stimuli.
Repeat tests at > 2 weeks
Type O blood normally has the lowest levels
Platelet levels tend to be normal, PT should be normal.
Diagnosis
VWF antigen level VWF:Ag (Quantity of VWF present in plasma; <50 are considered to be low)
VWF ristocetin cofactor assay (Efficacy of this plasma VWF in its ability to bind platelets in the presence of antibiotic ristocetin).
Measurement of coagulation factor VIII (FVIII:C)
Ratio of VWF:RCo/VWF:Ag (differentiate VWD type 1 and 2)
#Petechiae #Purpura #Bruise #ecchymosis #thrombocytopenia #Hematomas #blanching
Satyendra Dhar MD, @DharSaty
Approach to Thyroid Function Tests in the Evaluation of Hyperthyroidism
• Low TSH, Low normal T4 → Possibly Central Hypothyroidism. unlikely subclinical hyperthyroidism.
• Low TSH, normal T4 +/- T3 → Subclinical Hyperthyroidism: Work-up similar to hyperthyroidism as below. Can repeat labs 6 weeks after the resolution of pregnancy, critical illness, and dopamine agonists/octreotide.
• Low TSH, high T4 +/- T3 → Primary Hyperthyroidism
→ Signs of symmetrically enlarged thyroid & ophthalmopathy → Graves' Disease → Confirm with TRAb
→ Radioactive Iodine Uptake & Scan
• High or normal TSH, high T4 +/- T3 → Central (secondary) Hyperthyroidism → MRI Pituitary
- Dr. Claire Brickson @crbricks
#Hyperthyroidism #algorithm #diagnosis #endocrinology #TFTs #TSH #Interpretation
Diabetic foot infections (DFIs) is a common complication of longstanding diabetes, and it is associated with considerable morbidity, increased risk of lower extremity amputation, and a high mortality rate. The development of DFI derives from a complex interplay among peripheral neuropathy, peripheral arterial disease (PAD), and the immune system.
Most DFIs are polymicrobial, with aerobic gram-positive cocci, and especially staphylococci, the most common causative organisms. Aerobic gram-negative bacilli are frequently co-pathogens in infections that are chronic or follow antibiotic treatment, and obligate anaerobes may be co-pathogens in ischemic or necrotic wounds.
Empiric antibiotic therapy can be narrowly targeted at aerobic gram-positive cocci in many acutely infected patients, but those at risk for infection with antibiotic-resistant organisms or with chronic, previously treated, or severe infections usually require broader spectrum regimens. Imaging is helpful in most DFIs; plain radiographs may be sufficient, but magnetic resonance imaging is far more sensitive and specific.
Osteomyelitis occurs in 15% of ulcers, and 15% of those will go on to require amputation. Approximately 60% of patients undergoing lower extremity amputation have diabetic foot ulcers as the underlying cause. Following a lower extremity amputation, the 5-year mortality jumps to 60%.
Surgical interventions of various types are often needed, and proper wound care is important for successful cure of the infection and healing of the wound. Patients with a DFI should be evaluated for an ischemic foot, and employing multidisciplinary foot teams improves outcomes.
The prognosis for a diabetic foot infection depends on many factors including vascular blood supply and the presence of neuropathy.
Satyendra Dhar MD. @DharSaty
#Diabeticfootinfections #DFIs #Diabetes #ulcer #osteomyelitis
Ascites - Diagnostic Approach and Differential Diagnosis
The most common causes: cirrhosis, malignancy and heart failure. Approx 5% of patients w/ ascites have more than one cause (e.g. cirrhosis + TB, peritonitis, peritoneal carcinomatosis, HF, etc.).
Physical Exam:
1) Most relevant findings: Fluid wave (LR 5.3), peripheral edema (LR 3.8) / absence of edema (LR 0.17), shifting dullness (LR 2.1) - fluid wave/shifting dullness detect > 1 litre of ascites.
2) Other findings: bulging flanks, flank dullness, puddle sign, auscultatory percussion, abdominal wall hernias (umbilical, inguinal, incisional).
3) Signs of underlying disease: Cirrhosis, Malignancy, Heart Failure
Labs + Ascitic Fluid Analysis:
1) General appearance: Uncomplicated ascites: clear, pale straw-colored yellow, infection: hazy, cloudy or bloody fluid; hemorrhagic: frank blood; chylous: milky fluid; brown: elevated bilirubin
2) Routine tests: Cell count and differential, albumin and total protein concentration
3) Optional tests: Culture in blood culture bottles (infection, bowel perforation), glucose concentration (malignancy, infection, bowel perforation), LDH (malignancy, infection, bowel perforation), gram stain (suspected bowel perforation), amylase concentration (pancreatic ascites or bowel perforation), TB smear/culture/ADA (TB peritonitis), cytology/CEA antigen (malignancy), triglyceride (chylous ascites), bilirubin
concentration (bowel or biliary perforation), Serum pro-brain natriuretic peptide (heart failure)
Dr. Jorge Cortés @Jcortesizaguirr
#Ascites #workup #Differential #Diagnosis #hepatology
