Investigations Flashcards
Investigation
Acromegaly
- Serum IGF-1;
- Oral glucose tolernce test (+ve, failure of suppression of GH after 75g of oral glucose load);
- pit function tests: 9am cortisol, free T4 and TSH, LH/FSH, testosterone, prolactin;
- MRI of brain
Investigation
Adrenal insufficiency
- Dx: 9am serum cortisol (<100nmol/L and >550 makes it unlikely) or short Synacthen test (IM 250 ug tetrocosactrin - synth ACTH, serum cortisol <550nmol/L at 30 min = adrenal failure)
- ID level of defect -> High in 1ry disease, Low in 2ry and Long synacthen test (1mg synth ACTH admin, measure serum cortisol at 0, 30, 60, 90 and 120 min and then measure again at 4, 6, 8, 12 and 24hrs; pts with 1ry show no increase after 6hrs)
- ID the cause = AutoAb (against 21-OHase), abdoCT/MRI, other tests (adrenal biopsy, culture, PCR)
- Check TFTs
- In addisonian crisis = FBC, U+E (high urea, low Na, high K), CRP/ESR, Ca, glucose (low), blood cultures, urinalysis, culture and sensitivity
Investigation
Alcohol dependence
- Bloods: macrocytic anaemia, high GGT, AST/ALT, others: high uric acid, triglycerides, markers of organ damage
- Acute overdose: blood alcohol, glucose, ABG, U+Es, tox screen - drug OD
Investigation
Disseminated intravascular coagulation
- Bloods: FBC - low platelets/Hb/fibrinogen, high APTT/PT/fibrin degradation products/D-dimers
- Peripheral blood film: schistocytes
Investigation
HF
- Bloods -> FBC, U&E, LFT, CRP, Glucose, lipids, TFT, (ALVF: ABG, BNP^ and troponin);
- CXR -> Alveolar shadowing, Kerley B lines, Cardiomegaly, upper lobe Diversion, pleural Effusion;
- ECG -> normal?, ischaemic changes or arrhythmia/LV hypertrophy;
- EchoCG -> assess ventricular contraction, sys function = LV ejection fraction <40%, diastolic = restrictive filling defect;
- swan-ganz catheter = measurement of right atrial, right ventricle, pulm artery/wedge and LV end-diastolic pressures
Investigation
Multiple Sclerosis
- Dx is based on the finding of 2 or more CNS lesions with corresponding syx separated in time and space (McDonald criteria);
- LP = microscopy and CSF electrodes showing unmatched oligoclonal bands);
- MRI brain, cervical and thoracic spine, plaques can be identified and gadolinium enhancement shows active lesions;
- evoked potentials: visual, auditory and somatosensory evoked potentials may show delayed conduction velocity
Investigation
Pancreatic cancer
- Bloods = CA19-9, CEA is elevated,
- obstructive jaundice = high bilirubin/ALP/deranged clotting;
- imaging = USS, CT w/out guided biopsy, MRI/MRCP, ERCP (may allow biopsy bile, cytology and stenting)
Investigations
infective endocarditis
- Bloods: FBC (high neutrophils, normocytic anaemia), high ESR/CRP, U&Es - also tend to be Rheumatoid factor positive
- Urinalysis: microscopic hameaturia, proteinuria
- Blood culture: microscopy and sensitivities
- EchoCG: Transthoracic/transoesophageal
- Duke’s classification: Dx infective endocarditis based on findings of investigations and S&S
Investigations
Glomerulonephritis
- Bloods = FBC, U&Es and creatinine, LFTs, lipid profile, complement studies,
- Ab = ANA, anti-dsDNA, ANCA, anti-GBM ab, cryoglobulins;
- urine = microscopy, 24hr collection (creatinine clearance and protein);
- imaging = renal tract USS to exclude other pathology;
- renal biopsy = microscopy;
- investigations for associated conditions (HBV, HCV and HIV serology)
Investigations
1ry hyperaldosteronism
- Screening tests: low serum K (normal sNa), High urine K, high plasma aldosterone concentration, high aldosterone:renin activity ratio;
- confirmatory tests:
- Salt loading: failure of aldosterone suppression following salt load = 1ry
- postural test = measure plasma aldosterone, renin activity and cortisol when pt lying down at 8am, then measure again after 4hrs of pt being upright =
- aldosterone-producing adenoma = aldosterone decreases between 8am-12pm;
- bilat adrenal hyperplasia = adrenals respond to standing posture and increase renin production, increasing aldosterone production
- CT/MRI
- Bilat adrenal vein catheterisation = measuring aldosterone levels to distinguish between Conn’ sand BAH
- Radiolabelled cholesterol scanning = unilat uptake in adrenal adenomas, bilat uptake in BAH
Investigations
AAA
- Bloods -> FBC, clotting screen, renal/liver function and cross match if surgery planned;
- US to detect AAA,
- CT with contrast for rupture check,
- MRI angiography
Investigations
Achalasia
- CXR: widened mediastinum, double right heart border, air fluid level in upper chest, absence of normal gastric air bubble
- Barium swallow: dilated oesophagus, smooth taper down to the sphincter
- Endoscopy to exclude malignancy, mimic achalasia
- Manometry: to assess pressure at LOS = elevated resting LOS pressure, incomplete LOS relaxation, absence of peristalsis in SM portion of oesophagus
- Can do serology for Ab for chagas disease
Investigations
Acute cholangitis
- Bloods: FBC high WCC, CRP/ESR ?raised, LFTs: obstructive jaundice so raised ALP and GGT;
- U+Es:sx of renal dysfunction;
- blood culture for sepsis;
- amylase raised if lower part of common bile duct involved
- Imaging: XR KUB for stones;
- Abdo USS for stones and dilation of common bile duct;
- contrast enhanced CT/MRI for dx;
- MRCP: necessary for non-calcified stones
Investigations
Acute Kidney Injury
- Urinalysis = blood (nephritic), leucocyte esterase and nitrites (UTI), glucose, protein, urine osmolality;
- Bloods = FBC, blood film, U&Es, clotting, CRP, Immunology - sIg, ANA, complement, anti-GBM, antistreptolysin-O Ab, virology - hepatitis and HIV;
- US for postrenal cause and hydronephrosis;
- CXR pulm oedema,
- AXR renal stones
Investigations
Acute lymphoblastic leukaemia
- Bloods: FBC is normochromic normocytic anaemia, low platelets, variable WCC, high uric acid, high LDH, clotting screen
- Blood film: abundant lymphoblasts
- Bone marrow aspirate or trephine biopsy: hypercellular with >20% lymphoblasts
- Immunophenotyping: using Ab to recognise cell surface antigens
- Cytogenic - karyotyping to look for chromosomal abnormalities or translocations
- Cytochemistry
- LP: check CNS involvement
- CXR: may show mediastinal lymphadenopathy, lytic bone lesions
- Bone radiographs: mottled appearance with punched out lesions due to leukaemic infiltration
Investigations
Acute myeloblastic leukaemia
- Bloods: FBC - low Hb, low platelets, variable WCC, high uric acid, high LDH, clotting studies, fibrinogen, D-dimers
- Blood film: myeloblasts
- Bone marrow aspirate or biopsy: hypercellular with >20% blasts
- Immunophenotyping - Ab agaisnt surface Ag used to classify the lineage of the abnormal clones
- Cytogenetics
- Immunocytochemistry
Investigations
Acute pancreatitis
- Blood: very high serum amylase, high WCC, U+Es, high glucose, high CRP, low Ca, LFTs, ABG
- USS: evidence of gallstones in biliary tree
- Erect CXR Pleural effusion or bowel perf
- AXR: exclude other acute abdo
- CT scan
Investigations
AF
- ECG (uneven baseline, absent p waves, irreg intervals between QRS; atrial flutter = saw toothed appearance);
- Bloods (cardiac enzymes, TFT, lipid profile, U&E/Mg2+/Ca2+);
- EchoCG (mitral valve disease, left atrial dilatation, left ventricular dysfunction, structural abnormalities)
Investigations
Alcoholic hepatitis
- Bloods: FBC: low Hb, high MCV, high WCC, low platelets;
- LFTS: high AST/ALT, high bilirubin, high ALP/GGT, low albumin;
- U+Es: urea and K tend to be low;
- clotting: prolong PT
- US: other liver impairment causes
- Upper GI endoscopy: investigate varices
- Liver biopsy: distinguish from other causes of hepatitis
- EEG: slow wave activity = encephalopathy
Investigations
Amyloidosis
- Tissue biopsy;
- urine (check for proteinuria, free IG light chains in AL);
- Bloods: CRP/ESR, RhF, Ig levels, serum protein electrophoresis, LFTs, U+Es;
- SAP scan - radiolabelled SAP will localise the deposits of amyloid
Investigations
Anaphylaxis
- Clinical dx; serum tryptase, histamine levels or urinary metabolites of histamine may help support the clinical dx
- Following an attack: allergen skin testing IDs allergen;
- IgE immunoassays, finding food specific IgE in serum
Investigations
Ankylosing spondylitis
- Bloods: FBC - anaemia of chronic disease, RhF, ESR/CRP is high;
- radiographs: AP and lat radiographs of the spine (bamboo spine; symmetrical blurring of joint margins);
- later stages: Erosions, sclerosis, sacroiliac joint fusion;
- CXR: check for apical lung fibrosis
- LFTs: assess mechanical ventilatory impairment due to kyphosis
Investigations
Anti-phospholipid syndrome
- FBC - low platelets;
- ESR usually normal;
- U+Es can get APL nephropathy;
- clotting screen - high APTT;
- Presence of antiPL Ab may be demonstrated by: ELISA testing for anticardiolipin ab, lupus anticoagulant assays
Investigations
Aortic dissection
- Bloods: FBC, X match 10u of blood, U&E, clotting screen;
- CXR (widened mediastinum),
- ECG (normal unless LV hypertrophy/ inf MI signs),
- CT thorax
- EchoCG,
- Cardiac cath and aortography
Investigations
Aortic regurg
- CXR (cardiomegaly, dilatation of asc aorta, sx of Pulm oedema),
- ECG (LV hypertrophy: deep S in V1/2, Tall R in V5/6, inverted T in I/aVL/V5/6, L axis dev),
- EchoCG (underlying path, monitor progression and see size),
- Cardiac catheter with angiography
Investigations
aortic stenosis
- ECG: LV hypertrophy shown (deep S in V1/2, tall R in V5/6, inverted T in 1/aVL/V5/6, L axis deviation) and LBBB
- CXR (post-sternotic enlargement of asc aorta, calcification of aortic valve);
- EchoCG (assesses LV function);
- cardiac angiography (DDx from angina/MI
Investigations
Aplastic anaemia
- Bloods: FBC: low Hb/platelets/WCC/absent reticulocytes, normal MCV
- Blood film to exclude leukaemia (abnormal circ WBC)
- Bone marrow trephine biopsy
- Fanconi’s anaemia - increased chromosomal breakage in lymphocyte cultures in presence of DNA cross linking agents
Investigations
Appendicitis
- Bloods: high WCC and CRP;
- US may help;
- CT for dx
Investigations
ARDS
- CXR: bilat alveolar infiltrates and interstitial shadowing
- Bloods: figure out cause, FBC, U+Es, LFT, ESR/CRP, amylase, ABG, blood culture, sputum culture, plasma BNP <100 pg/mL distinguish ARDS from HF
- Echo: severe dysfunction of aortic/mitral valve, low left ventricular ejection fractions = haemodynamic oedema rather than ARDS
- Pulm artery catheterisation: check pulm cap wedge pressure
- Bronchoscopy: if cause not from hx
Investigations
Arterial Ulcer
- Duplex US of lower limbs,
- ankle-brachial pressure index,
- percutaneous angiography,
- ECG,
- Fasting serum lipids/blood glucose and HbA1c,
- FBC
Investigations
Aspergillus lung disease
- Aspergilloma:
- CXR = round mass with crescent of air around it;
- CT/MRI if CXR unclear; sputum culture could be negative
- ABPA:
- immediate skin test reactivity to asp Ag, eosinophilia, raised total sIgE and specific sIgE and IgG to A. fumigatus;
- CXR = transient patchy shadows, collapse, distended mucous filled bronchi,
- complications = fibrosis in upper lobes and bronchiectasis;
- CT = lung infiltrates and central bronchiectasis;
- lung function tests = reversible airflow limitation and reduced lung volumes/gas transfer
- Invasive aspergillosis:
- cultures/histological exam;
- broncheoalveolar lavage fluid/sputum may be used diagnostically;
- Chest CT = nodules with halo sign,
Investigations
Aspirin OD
- Bloods: salicylate levels, FBC,
- U+Es check for hypoK,
- LFTs high AST/ALT,
- clotting screen - high PT,
- other drug levels (paracetamol),
- ABG - mixed met acidosis and resp alk
- ECG: Sx of hypoK - flattened/inverted T waves, U waves, prolonged PR interval, ST depression
Investigations
Asthma
- Acute: peak flow, pulse oximetry, ABG, CXR, FBC (WCC raised if infective exacerbation), CRP, U&Es, blood and sputum cultures
- Chronic: peak flow monitoring (diurnal variation with dip in the morning), pulm function test, bloods: eosinophilia, IgE level, asp Ab titres, skin prick tests (ID allergens)
Investigations
Autoimmune hepatitis
- Bloods: LFTs: high: AST/ALT/GGT/ALP/bilirubin, low: albumin (severe);
- Clotting: high PT;
- FBC: low Hb, platetes and WCC;
- hypergammaglobulinaemia: presence of ANA, ASMA and anti-LKM Ab
- Liver biopsy: needed to establish dx and check hepatitis vs cirrhosis
- Rule out other causes of liver disease: viral serology, urinary copper/caeruloplasmin, ferritin and transferrin saturation, alpha-1 antitrypsin, anti-mitochondrial antibodies
- US/CT/MRI of liver and abdo: visualise structural lesions
- ERCP: rule out PSC
Management
Barett’s oesophagus
- Premalignant/high grade dysplasia: oesophageal resection, eradicative mucosectomy
- Other techniques: endoscopic targeted mucosectomy, mucosal ablation by epithelial laser, radiofrequency or photodynamic ablation
- Low-grade dysplasia: annual endoscopic surveillance is recommend
- No pre-malingant changes found: surveillance endoscopy and biopsy performed every 1-3yrs, anti-reflux measures
Investigations
Behcet’s disease
- Dx very clinical;
- pathergy test = needle prick becomes inflamed and a sterile pustule develops within 48hrs;
- can measure complement levels and check for a positive FHx
Investigations
Benign breast disease
- Triple assessment: clinical examination
- Imaging: mammography (2-view), US in younger pts
- Cytology/histology: fine needle aspiration - sent for cytological analysis; excision biopsy - sent for hitological analysis
Investigations
Biliary colic
- Urinalysis, CXR, ECG to exclude other causes;
- US: look for dilatation of CBD, gallbladder wall may be thickened;
- LFT; ERCP dx and therapeutically;
- CT: may be useful if other forms of imaging have been insufficient
Investigations
BPH
- Urinalysis = for UTI and blood;
- Bloods = U&Es for renal and PSA;
- midstream urine (MC&S);
- Imaging = US of urinary tract (hydronephrosis), bladder pre and post voiding, trans-rectal USS for bladder size and vol;
- flexible cystoscopy
Investigations
BPPV
Hallpike tests
Investigations
Breast abscess
USS, MC+S of pus samples
Investigations
Breast Cancer
- Triple assessment =
- clinical assessment,
- imaging = US (<35) OR mammogram (>35),
- tissue diagnosis = fine needle aspiration OR core biopsy;
- Sentinel LN biopsy (radioactive tracer injected into tumour, ID sentinel LN and then biopsy node for spread);
- staging = CXR, liver US, CT (brain/thorax);
- bloods = FBC, U&Es, Ca, bone profile, LFTs, ESR
Investigations
Bronchiectasis
- Sputum for culture and sensitivity = P. aeruginosa, H influenzae, S aureus, strep pneumo, klebsiella, mycobacteria;
- CXR = dilated bronchi, fibrosis, atelectasis, pneumonic consolidations;
- High res CT shows bronchi dilated with thick walls;
- bronchography;
- sweat electrolytes for CF, serum Ig, mucociliary clearance study
Investigations
Burns injury
- Bloods: O2 sat, ABG, carboxyHb (inhalation injury), FBC, U+E, Group and save
- Serum CK, urine myoglobin (check muscle damage), ECG
Investigations
Candidiasis
- Oral candidiasis - swabs and cultures not particularly useful as in many people’s mouths
- Swabs relevant for drug resistance check;
- therapeutic trials of anti-fungal can help with dx
- Oesophageal candidiasis definitive dx by endoscopy
- Invasive candidiasis: blood cultures required if candidaemia is possible
Investigations
Carcinoid syndrome
- 24 hr urine collection (check 5-HIAA levels),
- bloods (plasma chromogranin A/B and fasting gut hormones), CT/MRI scan (localise tumour),
- radioisotope scan (radiolabelled somatostatin analogue helps localise the tumour),
- investigations for MEN-1
Investigations
Cardiomyopathy
- CXR,
- ECG (ST changes, conduction defects, arrhythmia, hypertrophic - left axis deviation, signs of LV hypertrohpy, Q waves in inferior/lat leads; restrictive - low voltage complexes),
- EchoCG
- dil ventricles with global hypokinesia;
- hypertrophic = in ventricle, assymetrical septal hypertrophy;
- restrictive = non-diil/hypertrophied ventricles, atrial enlargement, preserved sys function, diastolic dysfunction, granular/sparkling appearance of myocardium in amyloidosis
- cardiac catheterisation,
- endomyocardial biopsy,
- pedigree/genetic analysis
Investigations
Carpal Tunnel syndrome
- Bloods: TFTs, ESR;
- Nerve conduction study: shows impaired median nerve conduction across the carpal tunnel
Investigations
Cellulitis
- Bloods: WCC, blood culture
- Discharge: sample and send for MC&S
- Aspiration - if pus suspected
- CT/MRI - orbital cellulitis is suspected (helps assess posterior spread of infection
Investigations
Cervical spondylosis
- Spinal XR (lat - can detect OA change, rarely dx if non-traumatic);
- MRI: allows assessment of root and cord compression, helps exclude spinal cord tumour and nerve root infiltration by granulomatous tissue;
- needle EMG
Investigations
Cholangiocarcinoma
- Bloods = FBC, U+Es, LFTs (high ALP and GGT),
- clotting screen,
- tumour markers (CA19-9 is marker of pancreatic cancer and cholangiocarcinoma);
- endoscopy;
- USS, CT, MRI,
- Bone scan for staging
Investigations
Cholecystitis
- Bloods: FBC - high WCC in cholecystites and cholangitis;
- LFT high ALP/GGT;
- blood cultures;
- amylase
- US: show gallstones, increased thickness of gallbladder wall, dilatation of biliary tree
- AXR: but only 10% of gallstones are radioopaque
- Other imaging - to exclude differentials
Investigations
Chronic Kidney disease
- Assess renal function = urea (not good, varies with diet/hydration), creatinine (useful but limitations), isotopic GFR (expensive but gold standard);
- biochem = glucose, K (raised), check Na, HCO3, Ca, PO4;
- serology = Ab (ANA, c-ANCA, anti-GBM), hepatitis, HIV;
- Urinalysis = check for proteinuria/haematuria, check for 24hr urine collection, serum/urine protein electrophoresis;
- imaging = USS, CT/MRI, XR KUB; renal biopsy
Investigations
Chronic lymphocytic leukaemia
- May be associated with AI, such as haemolytic anaemia or thrombocytopaenia
- Bloods: FBC; lymphocytosis, low Hb (bone marrow infiltration, hypersplenism, autoimmune haemolysis), low platelets, low serum Ig
- Blood film: small lymphocytes with thin rims of cytoplasm, smudge cells
- Bone marrow aspirate or biopsy - lymphocytic replacement of normal marrow
- cytogenetics
Investigations
Chronic myeloid leukaemia
- Bloods: FBC: high WCC, low Hb, high basophils/neutrophils/eosinophils;
- high/normal/low platelets, high uric acid, high B12 and transcobalamin
- Blood film: immature granulocytes
- Bone marrow aspirate or biopsy: hypercellular with raised myeloid-erythroid ratio
- Cytogenetics: show the philadelphia chromosome
Investigations
Chronic pancreatitis
- Bloods: high glucose (OGTT), amylase/lipase normal, high Ig
- US
- ERCP/MRCP: early changes = main duct dilatation and stumping of branches;
- late changes = duct strictures with alternating dilatation
- Abdo XR: calcification of pancreas
- CT scan: same as AXR
- Test of pancreatic exocrine function: faecal elastase - pacreatic exocrine function
Investigations
Cirrhosis
- Bloods: FBC: low pts+Hb, LFTs: normal but often high AST/ALT/ALP/GGT/bilirubin, low albumin;
- clotting: prolonged PT;
- serum AFP: raised chronic liver disease, high levels suggest hepatocellular carcinoma
- To determine cause: viral serology, A1anti-trypsin, caeruloplasmin, iron studies for haemochromatosis, anti-mitochondrial Ab, ANA/ASMA
- Ascitic tap: MC+S, biochem, cytology, ascitic tap w/neutrophils >250/mm3 = spontaneous bacterial peritonitis
- Liver biopsy: performed percutaneously, transjugular;
- histopathological features of cirrhosis: periportal fibrosis, loss of normal liver architecture, nodular appearance;
- Grade: indicates degree of inflammation;
- Stage: degree of architectural distortion
- Imaging: US, CT, MRI for ascites, HCC, hepatic/portal vein thrombosis, exclude biliary obstruction; MRCP
- Endoscopy - varices
- Child pugh grading: score for estimating prognosis in chronic liver disease/cirrhosis: albumin, bilirubin, PT, ascites encephalopathy;
- cirrhosis divided into classes using: Class A: 5-6, Class B: 7-9, Class C: 10-15
Investigations
Coeliac disease
- Blood: FBC (low Hb, iron, folate), U+Es, albumin, calcium, Phosphate
- Serology: IgG anti-gladin Ab, IgA and IgG anti-endomysial tranglutaminase Ab can be dx;
- IgA def quite common
- Stool: culture to exclude infection, faecal fat tests for steatorrhoea
- D-xylose test: reduced urinary excretion after oral xylose indicates small bowel malabsorption
- Endoscopy: direct visualisation of vilous atrophy in the small intestine, villous atrophy and crypt hyperplasia in duodenum
Investigations
Colorectal cancer
- Bloods = FBC (anaemia), LFTs, tumour markers (CEA);
- Stools FOBT as screening test;
- endoscopy can be used to biopsy tumour;
- double contrast barium enema (apple core strictures),
- contrast CT for Duke’s staging
Investigations
Constrictive pericarditis
- CXR (calcification on pericardium),
- echoCG,
- MRI (thickness of pericardium),
- CT, pericardial biopsy (ifi infective cause)
Investigations
COPD
- Spirometry and pulm function tests (reduced PEFR/FEV1/FVC, increased lung volumes and decreased CO gas transfer coefficient);
- CXR = normal, hyperinflation, reduced peripheral lung markings, elongated cardiac silhouette;
- bloods = FBC = increased Hb and Hct due to 2ry polycythaemia;
- ABG;
- ECG and echo;
- sputum and blood cultures (in acute infective exacerbations);
- alpha 1 antitrypsin levels
Investigations
Crohn’s disease
- Blood: FBC - low Hb, high platelets, high WCC; U+Es, LFTs - low albumin; high ESR, CRP may be high or normal
- Stool microscopy and culture: exclude infective colitis
- AXR to show toxic megacolon; erect CXR if there is a risk of perf
- Small bowel barium follow through - fibrosis/strictures, deep ulceration, cobblestone mucosa
- Endoscopy and biopsy: for UC vs CD;
- useful for monitoring malignancy and disease progression;
- show mucosal oedema and ulceration with rose thorn fissures;
- fistulae and abscesses;
- transmural chronic inflammation of macrophages, lymphocytes and plasma cells;
- granulomas with epitheliod giant cells may be seen in blood vessels and lymphatics
- Radionuclide labelled neutrophil scan: can localise the inflammation
Investigations
Cushing’s syndrome
- Must be performed on pts with high pretest probability;
- bloods (U+Es hypoK due to mineralocorticoid effect, BM high glucose)
- Initial high sensitivity tests = urinary free cortisol, late night salivary cortisol, overnight/low dose dexamethasone suppression test (give 0.5mg DXM orally every 6hrs for 48hrs; failure to suppress below 50 nmol/L)
- Test to determine underlying cause:
- ACTH independent -> low plasma ACTH, CT/MRI of adrenals
- ACTH dependent -> high plasma ACTH, pit MRI, high-dose DXM suppression test, inferior petrosal sinus sampling (superior to HDDST)
- ACTH dependent ectopic -> lung cancer = CXR, sputum cytology, bronchoscopy, CT scan; radiolabelled octreotide scans can detect carcinoid tumours because they express somatostatin receotirs
Investigations
Depressive disorder
- Consider organic causes - hypothyroidism, hypercalcaemia, addisons disease, cushing’s disease
- Inv for other causes: blood glucose, U+Es, TFT, Cal, FBC, MRI/CT
Investigations
Diabetes insipidus
- Bloods: U+Es, Ca, increased plasma osm, decreased urine osm
- Water deprivation test = restricted for 8hrs;
- plasma and urine osm measured every hour for 8hrs;
- weigh the pt hourly to monitor level of dehydration;
- STOP the test body weight fall >3%.
- Desmopressin given after 8hrs and urine osm measured
- Results = normal (water restriction causes): increased plasma osm, ADH secretion, water reabsorption, urine osm (>600mosmol/kg);
- DI: Lack of ADH so urine osm LOW (<400), cranial means urine osm rises >50% after Desmopressin, nephrogenic means urine osm rises <45% after desmo
Investigations
Diverticular disease
- Bloods: FBC increased WCC and CRP, check clotting and cross-match if bleeding
- Barium enema: shows presence of diverticulae (saw tooth appearance of lumen);
- reflects psuedohypertrophy of circular muscle
- Flexible sigmoidoscopy and colonoscopy: diverticulae can be visualised and other pathology can be excluded
- ACUTE: CT scan for evidence of disease and complications may be performed
Investigations
DMT1
- Blood glucose - fasting >7 or random bgl >11;
- HBA1c;
- FBC: MCV reticulocytes; U+Es monitor for nephropathy and hyperkalaemia; lipid profile;
- urine albumin creatinine ratio to detect microalbuminuria;
- urine - glycosuria, ketonuria, MSU;
- Investigations for DKA: FBC (raised WCC w/out infection), U+Es (raised urea/creatinine ), LFT, CRP, glucose, amylase, blood cultures, ABG (met acidosis with high anion gap), blood/urinary ketones
Investigations
DVT
Doppler US,
impedance plethysmography,
bloods (d-dimer as -ve predictor and thrombophilia screen if indicated, if PE = ECG, CXR, ABG)
Investigations
Eczema
- Contact eczema: skin patch testing - disc containing allergens is diluted and applied on skin for 48hrs - if red raised lesion = positive
- Atopic eczema: lab testing - IgE level
Investigations
Encephalitis
- Bloods -> FBC, U+Es, glucose, viral serology, ABG;
- MRI/CT -> exclude mass lesion, HSV causes oedema of temporal lobe on MRI;
- Lumbar puncture -> high lymphocytes/monocytes/protein, glucose normal, viral PCR;
- EEG -> epileptiform activity;
- brain biopsy rarely needed
Investigations
Epididymitis and orchitis
- Urine = dipstick, early morning urine collections for MC&S;
- Bloods = FBC for WCC, high CRP,
- U&Es; imaging = increased blood flow on duplex examination
Investigations
Epilepsy
- Bloods -> FBC, U+Es, LFT, glucose, Ca, Mg, ABG, toxicology screen, prolactin;
- EEG -> helps to confirm dx, helps classify epilepsy;
- CT/MRI -> structural, space occupying or vascular lesions;
- other due to 2ry causes
Investigations
Erythema multiforme
- Usually unnecessary - erythema multiforme - clinical dx; Bloods: high WC, eosinophils, ESR/CRP
- Imaging: exclude sarcoidosis and atypical pneumonia
- Skin biopsy: histology and direct immunoflourescence if in doubt
Investigations
Erythema nodosum
- Determine cause;
- bloods: anti-streptolysin O titres, FBC/CRP/ESR, U+Es, serum ACE (^ in sarcoidosis)
- Throat swab and cultures
- Mantoux/head skin testing for TB
- CXR for bilat hilar lymphadenopathy/TB/sarcidosis/fungal infections sx
Investigations
Extradural haemorrhage
- Urgent CT scan: check for haematoma, look for features of raised ICP - midline shift
Investigations
extrinsic allergic alveolitis
- Bloods = FBC (neutrophilia, lymphopoenia), ABG reduced PO2/CO2;
- serology = IgG to fungal/avian Ag;
- CXR = normal in acute episodes, fibrosis seen in chronic cases;
- high res CT-thorax;
- pulm function tests = restrictive defect (low FEV1, low FVC, preserved/increased FEV1/FVC, reduced total lung capacity);
- bronchoalveolar lavage = increased cellularity, lung biopsy can be performed
Investigations
Fibromyalgia
- Clinical dx;
- key features: Widespread pain involving both sides of the body above and below the waist for at least 3m;
- presence of 11 tender points among 9 pairs of specific sites
Investigations
Gastric cancer
- Upper GI endoscopy;
- bloods = FBC (anaemia), LFTs;
- CT/MRI for staging,
- endoscopic USS - assess depth of gastric invasion and LN involvment
Investigations
Gastroenteritis
- Bloods: FBC, blood culture, U+Es
- Stool: faecal microscopy, analysis for toxins, pseudomembranous colitis
- AXR/US: exclude other causes of abdo pain
- Sigmoidoscopy: usually unnecessary unless IBD excluded
Investigations
Gastrointestinal perforation
- Bloods: FBC, U+Es, LFTs, amylase - raised with perf
- Erect CXR for air under diaphragm
- AXR: shows abnormal gas shadowing
- Gastrograffin swallow: for suspected oesophageal perf
Investigations
Giant cell arteritis
- Bloods: high ESR, FBC = normocytic anaemia of chronic disease;
- Temporal artery biopsy: must be performed within 48hrs of starting corticosteroids, negative biopsy doesn’t necessarily rule out GCA
Investigations
Glaucoma
- Goldmann applanation tonometry: standard method of measuring IOP, normal = 15mmHg
- Pachymetry: using US or optical scanning to measure central corneal thickness;
- CCT < 590mm = higher risk of glaucoma
- Fundoscopy: detects pathologically cupped optic disc
- Gonioscopy: assess iridocorneal angle
- Perimetry (visual field testing)
Investigations
Gout
- Synovial fluid aspirate: monosodium urate crystals seen = needle shaped, negative birefringence under polarised light microscopy, microscopy and culture also used to exclude septic arthritis
- Bloods: FBC riased WCC; U+Es, raised urate, raised ESR
- AXR/KUB film -> uric acid renal stones may be seen
Investigations
GORD
- Clinical dx
- Upper GI endoscopy, biopsy, cytological brushings to exclude malignancy
- Barium swallow - detects hiatus hernia (repair op = Nissen fundoplication), peptic stricture, extrinsic compression of oesophagus
- CXR: not specific for GORD but can lead to finding hiatus hernia = gastric bubble behind the cardiac shadow
- 24hr oesophageal pH monitoring: pH probe places in lower oesophagus determining relationship between syx and oesophageal pH
Investigations
Graves disease
- TFTs - low TSH and high T3/T4;
- autoantibodies - anti-TPO antibodies (75%), anti-thyroglobulin antibodies, TSH-receptor ab (very sensitive/specific for graves);
- imaging - thyroid US, thyroid uptake scan;
- inflammatory markers - CRP/ESR raised in subacute thyroiditis
Investigations
Guillain Barre Syndrome
- Lumbar puncture = high protein, normal cell count and glucose;
- nerve conduction study = reduced velocity;
- bloods = anti-ganglioside Ab in miller-fisher variant +25% of other cases;
- spirometry = reduced FVC;
- ECG = arrhythmias may develop
Investigations
Haemochromatosis
- Haematinics: serum ferritin (high), transferrin (low), transferrin sat (high), TIBC (low);
- other tests to exclude: CRP (inflammation), chronic alcohol consumption, ALT (liver necrosis);
- LFTs;
- other investigations for abnormal liver fucntion, genetic testing, liver biopsy (RARE)
Investigations
Haemolytic anaemia
- Bloods: FBC = low Hb and haptoglobin, high reticulocytes/MCV/unconjugated bilirubin;
- U+Es, folate
- Blood film: leucoerythroblastic picture, macrocytosis, nucleated RBC/reticulocytes, polychromasia, may ID specific abnormal cells like: spherocytes, elliptocytes, sickle cells, schistocytes, malarial parasites
- Urine: high urobilinogen, haemoglobinuria, haemosiderinuria
- Direct coombs’ test: tests for AI haemolytic anaemia, Id RBC coated with Ab
- Osmotic fragility test or spectrin mutation analysis - Id membrane abnormalities
- Ham’s test - lysis of RBC in acidified serum in paroxysmal nocturnal haemoglobinuria
- Hb electrophoresis or enzyme assays to exclude other causes
- Bone marrow biopsy