Rapidly progressive glomerulonephritis (RPGN)

Guttate psoriasis

- distinctive acute eruption of small, drop-like, 1-10mm in diameter, salmon-pink papules, usually with a fine scale
- URTI from group A beta-hemolytic streptococci often precedes the eruption by 2-3 weeks
- primarily occurs on trunk and proximal extremities

Neuralgic amyotrophy

- a.k.a brachial neuritis, Parsonage-Turner syndrome, immune-mediated brachial plexus neuropathy (IBPN)
- occurs in response to bodily stress (surgery, flu, post vaccination)
- usually presents with an acute onset of severe pain in shoulder region
- intense pain usually last several days to weeks, but dull ache can persist
- as the pain dissipates, weakness and often sensory loss are appreciated
- scapular winging in common
- empirical treatment of severe pain with glucocorticoids is often used in the acute period
- this condition is usually self limiting (improve over weeks to months)

Orbital apex syndrome

- a.k.a Jacod syndrome
- collection of cranial nerve deficits associated with a mass lesion near the orbital apex region
- presents with proptosis, chemosis, optic neuropathy, Horner's syndrome, ophthalmoplegia, involvement of ophthalmic nerve (first branch of trigeminal nerve)

Subarachnoid hemorrhage

Friedreich ataxia

- autosomal recessive trinucleotide repeat disorder (GAA repeat)
- most common form of hereditary ataxia
- mutation in gene encoding protein frataxin on chromosome 9
- presents with progressive ataxia, cerebellar dysfunction, pyramidal weakness and sensory motor neuropathy
- other features: pes cavus, optic atrophy, hypertrophic cardiomyopathy (50-70% patients)

Alveolar-arterial gradient (A-a gradient)

Calculated A-a gradient = 150mmHg - PaCO2/0.8 - PaO2
Expected A-a gradient = Age/4 + 4


Normal A-a gradient suggest hypoventilation (hypoxia proportional to low ventilatory effort)
Increased A-a gradient suggest defect in diffusion, V/Q mismatch or right-left shunt

Monod's sign

Monod's sign: opacity surrounded by a crescent of air
- typical of aspergilloma (mycetoma) in a pre-existing air cavity (old tuberculosis, histoplasmosis, sarcoidosis, neoplasm)

Hereditary neuropathy

- Charcot Marie Tooth (CMT) disease is the most common type of hereditary neuropathy

CMT type 1 (AD)
- usually presents in the first to third decade of life with distal leg weakness (eg: footdrop)
- muscle stretch reflexes are unobtainable or reduced throughout
- pes cavus
- often atrophy of muscles below knee (inverted champagne bottle leg)
- nerve conduction is very reduced

CMT type 2 (AD)
- tends to present later in life compared to type 1 and much milder
- nerve conduction is only very slightly reduced or normal

CMT type 3 / Dejerine Sottas (AR)
- presenting in infancy or early childhood
- affected children are severely weak
- typically associated with enlargement of peripheral nerves

Actinomycosis

- indolent, slowly progressive infection caused by anaerobic or microaerophilic bacteria
- most commonly caused by A.israelii
- in vivo growth of actinomycetes usually results in the formation of characteristic clumps called grains or sulfur granules
- occurs most frequently at an oral, cervical or facial site as soft tissue swelling, abscess or mass lesion that is often mistaken for a neoplasm
- abdominal and pelvic actinomycosis usually follows introduction of organism through surgery or IUCD
- thoracic actinomycosis usually follows an indolent progressive course with involvement of pulmonary parenchyma and/or pleural space
- treatment: high dose IV benzylpenicillin and surgical resection/drainage

Cheiroarthropathy

- condition of limited joint mobility that occur in diabetics
- characterised by thickening of skin resulting in contracture of fingers
- unable to extend the fingers to fully flatten the hand
- treatment: pain relieve, phystiotherapy, tight glycemic control

familial hypercholesterolemia

- type IIA hyperlipidemia
- autosomal codominant disorder characterised by elevated plasma levels of LDL-C with normal triglyceride, tendon xanthomas and premature coronary atherosclerosis
- homozygous FH occurs in approximately 1 in 1 million persons worldwide, whereas heterozygous FH occurs in 1 in 500 persons
- most homozygous FH present in childhood with cutaneous xanthomas on hand, wrist, elbows, knees, heels, or buttocks. Total cholesterol levels are usually >500mg/dL and devastating complication of homozygous FH is accelerated atherosclerosis
- treatment for FH is LDL apheresis (homozygous) and statin in combination with cholesterol absorption inhibitor
- family history is usually positive for premature atherosclerotic cardiovascular disease