Clinical examination Flashcards
Lab abnormalities in depression
- dexamethasone suppression test
- Corticotrophic releasing hormone test
TSH
DST nonsuppression (DST-positive result) is seen in many disorders associated with depression e.g. major depressive disorder (44%), psychotic affective disorders
(69%), and in depression with serious suicidality (78%).
DST-positive patients respond more favourably to biological interventions.
DST non-suppression is nonspecific
- CRHT HP axis abnormality in major depression –> blunted ACTH response
~ 30% of depressed patients show blunted TSH response during depression
Diagnostic possibilities for panic attacks
- paroxysmal atrial tachycardia
- pulmonary embolus
- seizure disorder,
- Meniere’s disease
- transient ischemic attack
- carcinoid syndrome,
- Cushing’s disease
- hyperthyroidism
- hypoglycemia
- pheochromocytoma
lactate infusion and panic disorder
Nearly 72% patients with panic disorder have a panic attack when
administered IV injections of sodium lactate.
lactate provocation is used to confirm a diagnosis of panic disorder. Hyperventilation and CO2 inhalation have been used.
Panic attacks triggered by sodium lactate are not inhibited by peripherally acting beta-blockers but are inhibited by benzodiazepines and tricyclic drugs
Narcoanalysis
interview with amobarbital
- Organic conditions tend to worsen with infusions of amobarbital
- nonorganic or psychogenic conditions tend to get better because of disinhibition, decreased
anxiety, or increased relaxation.
- useful in disorders of repression and dissociation such as amnesia and fugue.
- Benzodiazepines can be
substituted for amobarbital.
Acute intermittent porphyria (AIP)
Disorders of haem metabolism, characterised by neurological and psychiatric manifestations
no rash + abdo pain, neuropathies and constipation.
Diclofenac can precipitate an episode.
Test = increase urinary porphibilnogen during attacks. tx = reduc haem sythentis, administed haemin
Autoimmune encephalitis presenting as psychosis
vulnerable receptors:
- Voltage Gated Potassium Channel complex (LGI1, CASPR2, contactin-2)
- N-Methyl-D-aspartate receptor (NMDA)
- AMPA receptor
- GABA-B
- Glycine receptor
Anti-NMDA receptor (NMDAR) encephalitis.
These antibodies result in destruction of synaptic NMDAR
through crosslinking and internalisation.
females > men
50% have underlying ovarian teratoma
prodromal - fever, headache, malaiae
tests
1. serum NMDAR and VGKC abodies
2. EEG and MRI brain
3. ANA, cRP, ESR, U+E (low NA)
4. CSF analysis
5. feamles US/CT pelvis
Treatment
1. 3 days methylprednisolone + 5 days plasma exchanfe and reminssion with steroid plus rituximab
Anorexia
- physical abnormalities
endocrine
- Low LH, FSH and oestradiol
-Low T3, T4 in low normal range, normal TSH (low T3 syndrome)
- Mild increase in plasma cortisol
- Raised growth hormone conc
- Severe hypoglycaemia (rare)
- Low leptin (but possibly higher than would be expected for bodyweight)
cardiovascular
- prolonged Q-T
GI- dlayed gastric emptying
Haem- normocytic anaemia, leucopenia, thormbocytopenia
BMI = kg / height in m squared. underweight is under 18.5
alcohol use disorder - most sensitive test for heavy use
Carbohydrate Deficient Transferrin
(CDT), the CDT is the single most specific and sensitive test for detecting heavy alcohol use over
last 10 days
Risk factors for prolonged QTc include
- Congenital long Q-T syndrome,
- Underlying heart disease, bradycardia, heart failure, and ischemic disease
- Female gender, Extremes of age,
- Presence of liver disease,
- Electrolyte abnormalities (hypokalemia, hypocalcemia and hypomagnesemia),
- Illicit drug use (principally stimulants),
- Starvation or anorexia,
- High physical exertion (agitation),
- High dosages of the drug contributing to the lengthened Q-T interval, and
- Rapid infusion of torsadogenic drugs
Renal disturbances in IV drug users:
Cocaine and heroin abuse are linked to various renal conditions such as nephrotic syndrome, acute glomerulonephritis, amyloidosis, interstitial nephritis, and rhabdomyolysis.
In heroin users, nephropathy may present with a puffy face, hypertension, and weight gain. Infective endocarditis, HIV, HBV, and HCV infections can cause renal damage similar to the effects of the drugs, with racial differences in glomerular pathologies (focal segmental glomerulosclerosis in Black patients and membranoproliferative glomerulonephritis in White patients)
SIADH and related disorders:
SIADH can be induced by antidepressants or antipsychotics, or by psychogenic polydipsia, where excessive water consumption occurs without an underlying organic cause. Diabetes insipidus may result from lithium (nephrogenic) or head injury (central).
Urine analysis is essential in diagnosing these conditions.
-standard screening instrument for
dementia
clock drawing test
addenbrookes (ACE)
MMSE: The Mini-Mental State Examination (MMSE)
introduced by Folstein in 1976
clock- watson.
addenbrookes-Frontal tests such as verbal fluency are also included in the ACE, making it more sensitive
to frontal types of dementia than MMSE
Magnetic Resonance Spectroscopy –MRS
Functional magnetic resonance imaging
It can detect several biologically important nuclei with an odd number of protons and neutrons.
e.g.measure concentrations of
psychotherapeutic drugs such as lithium in the brain
FMRI- is a Blood Oxygen Level Dependent (BOLD) technique
is a proxy measure of tissue activity
No radioactive isotopes are administered in fMRI
Single Photon Emission Computed Tomography - SPECT
uses radioactive compounds to study regional differences in cerebral blood flow. within the brain records the pattern of photon emission from the bloodstream which
varies according to the level of perfusion uses compounds labeled with single photon-emitting isotopes: iodine-123,
technetium-99m, and xenon-133.
