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, malaise
**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 = linked to nephrotic syndrome, acute glomerulonephritis, amyloidosis, interstitial nephritis, and rhabdomyolysis.
* Heroin –> nephropathy presents with = puffy face, hypertension, and weight gain.
* Infective endocarditis, HIV, HBV, and HCV infections can cause renal damage similar too
* racial differences in glomerular pathologies
* focal segmental glomerulosclerosis in Black patients
* membranoproliferative glomerulonephritis in White patients
SIADH and related disorders:
SIADH can be induced by antidepressants or antipsychotics,
* psychogenic polydipsia = excessive water consumption occurs without an underlying organic cause.
* Diabetes insipidus may result from lithium (nephrogenic) or head injury (central).
* Urine analysis = essential in diagnosing
-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.
Positron Emmission Tomography (PET)
Diffusion tensor imaging
- PET = used to study blood flow, receptor distribution and metabolic activity of brain tissue.
- 2 particles are emitted so more precise than SPECT. The most commonly employed ligand is [18F] fluorodeoxyglucose
DTI -combines the principles of nuclear magnetic resonance and molecular diffusion
* TI allows multiple (e.g. 16) gradients .
- From DTI, mathematical measures such as the Fractional Anisotropy (FA) can be calculated. = an index of the integrity of white matter.
Neuroimaging findings in depression
- Periventricular and deep WM hyperintensities
- Subcortical – thalamic and striatal hyperintensities
- Decreased frontal + basal ganglia volumes
- Decreased metabolism in prefrontal cortex, Anterior cingulate & amygdale
- Higher prefrontal metabolism (esp. anterior cingulate) predict better treatment response
- Higher 5HT2A receptor density – higher dysfunctional negative thoughts
- Increased MAO-A activity (F>M)
- Elevated D2 binding in untreated depression – psychomotor retardation
- Therapeutic dose of SSRIs- 80% 5HT transporters occupied
Neuroimaging findings in schizophrenia
- ventricular enlargement
- Loss of grey matter
- Progressive loss of brain volume in first few years of diagnosis
- fMRI reveals poor DLPFC activation in executive tasks
- Decreased NAA (N-Acetyl aspartate) in PFC (neuronal loss) in MRS
- Widespread reduction in DTI (diffusion tensor) – fractional anisotropy: frontal and corpus
callosum – more in chronic treated patients
Neuroimaging findings in Alzheimer’s
- Ventricular enlargement
- Loss of temporal lobe volume – especially hippocampus
- Decreased parieto-temporal fMRI activation and SPECT blood flow
Neuroimaging findings in OCD
- Both reduced and increased volumes of caudate nuclei reported.
- Higher caudate blood flow due to increased metabolism.
- This reduces after effective treatment of the OCD
Neuroimaging findings from childhood onset schizophrenia (COS)
- progressice reduction in frontal and temporal lobe.
- profound early reduction in parietal lobe in COS
- ventricular enlargement at baseline and slower growth rates of white matter are also noted
wilsons disease
known as?
ceruloplasmin is?
known as hepatocerebral degeneration
ceruloplasmin levels are typically low because of impaired copper transport
CU deposits - particularly in the lenticular nucleus, leading to neurological symptoms like tremors, dystonia, and parkinsonism. NOT dementia
what is a healthy weight to height ratio?
A ratio between 0.4 and 0.49 is generally considered healthy, as it indicates a lower risk of obesity-related health conditions.
Obsessions
Compulsions
obsessions → urges, images, or thoughts
Compulsions → acts (motor or mental)
elevated Vanillylmandelic acid in urine?
Elevated VMA in urine = associated with pheochromocytoma
