Other cases - general Flashcards
(56 cards)
Differences between open angle and closed angle glaucoma
Open angle Bilateral Initially asymptomatic Mild non specific symptoms Progressive visual loss
Closed angle Unilateral Sudden onset Severely painful N+V, cloudy cornea, headache, dilated pupil Reduced visual acuity
Differences between anterior uveitis and posterior uveitis
Anterior uveitis Unilateral Autoimmune conditions Painful, ocular hyperaemia Blurry vision Increased lacrimation + photophobia
Posterior uveitis Bilateral infective Painless Blurry vision Floaters + scotomata
Define conjuctivitis
Inflammation of the lining of the eyelids and eyeball caused by bacteria, viruses, allergic or immunological reactions, mechanical/irritative/toxic or medicines
Differences between bacterial and viral conjunctivitis
Bacterial conjunctivitis Unilateral Purulent discharge Reduced vision might have a Hx of STD Urethritis/vaginal discharge?
Viral conjunctivitis Bilateral Clear discharge Normal vision Signs of viral infection e.g. URT infection
Differences between acute angle glaucoma + acute anterior uveitis + conjunctivitis
Acute angle glaucoma • Extremely painful • Decreased VA • Photophobia • Systemically unwell – acute systemic malaise • Semi-dilated or oval pupil • Hazy cornea • Halos around eyes • increased IOP
Acute anterior uveitis • Painful • VA may be reduced • Photophobia • Constricted or irregular pupils • Cloudy aqueous humour (presence of inflammatory cells in aqueous humour) [hypopyon, flare, keratic precipitates] • decreased IOP
Conjunctivitis
• Not painful
• No photophobia
• VA normal
What is rheumatc fever?
autoimmune disease that may occur 1-5 weeks after a group A β-haemolytic streptococci throat infection (URTI, may present as a sore throat)
Peak incidence – 5-15 y/o
All manifestations (joints, chorea, erythema marginatum, SC nodules) of acute rheumatic fever resolve without sequale but carditis can lead to chronic rheumatic heart disease
Which are the 4 stages of the HIV infection?
Seroconversion illness • 1-6 weeks after infection • Infectious mononucleosis – like illness – fever, night sweats, malaise, myalgia, pharyngitis, headaches, diarrhoea, neuralgia neuropathy, lymphadenopathy, maculopapular rash • Antibody tests are negative • Viral p24 + HIV RNA are elevated
Asymptomatic infection
• 18 months to 15 years
• Persistent generalised lymphadenopathy - Nodes >1cm at 2 extra-inguinal sites persisting >3 months not due to any other cause
• Progressive minor symptoms – rash, oral thrush, weight loss, malaise
• CD4 + CD8 lymphocyte levels are normal (>500 cells/mm3)
• Virus levels are low but replication continues slowly
Symptomatic infection
• Nonspecific constitutional symptoms develop – fever, night sweats, diarrhoea, weight loss
• Minor opportunistic infections – candida, oral hairy leucoplakia, herpes zoster, recurrent herpes simplex, seborrheic dermatitis, tinea infections
• This collection of symptoms + signs is referred to as AIDS-related complex (ARC) + is regarded as a prodrome to AIDS
AIDS
• CD4 count <200 cells/microlitre
• Severe immunodeficiency
• Evidence of life-threatening infections + unusual tumours
• AIDS defining conditions start to occur
o Recurrent bacterial pneumonia
o Pneumocystis pneumonia
o Fungal infections (candidiasis of oesophagus)
o Kaposi sarcoma – HHV8
o Primary lymphoma of the brain
Most common causes of viral tonsilitis
rhinovirus, coronavirus, adenovirus
A 47-year-old HIV positive patient presents with weakness of his right leg, headaches, fever and confusion that have been getting worse for the last week. CT head shows multiple ring-enhancing lesions.
Causative organism
Toxoplasma gonidii
Associated with cats
In immunocompromised - myocarditis, encephalitis, focal CNS signs, stroke, seizures
Tests - ↑IgM in acute infection, ↑IgG and toxoplasma antigen titres in acute (not useful), lymph node/CNS biopsy
CT – characteristic multiple ring-shaped contrast enhancing lesions
• HIV, neuro symptoms, multiple brain lesions with ring enhancement – toxoplasmosis
Commonest virus causing common cold
Rhinovirus
Human herpesviruse and the conditions they cause
HHV1 HHV2 HHV3 HHV4 HHV5 HHV8
HHV1 - HSV1
Respiratory, saliva
Gingivostomatitis, keratoconjuctivits, herpes labialis, Temporal lobe encephalitis
HHV2 - HSV2
Sexual contact, perinatal
Genital herpes, Neonatal herpes
HHV3 - VZV
Respiratory
Chicken pox, shingles
HHV4 - EBV
Saliva - kissing disease
Mononucleosis (associated with lymphomas, nasopharyngeal carcinoma)
HHV5 - CMV
congenital, sexual, saliva
Mononucleosis in immunocompromised
HHV8 - HHV8
Sexual contact
Causes kaposi sarcoma in immunocompromised patients
Complications of infectious mononucleosis
• Nasopharyngeal carcinoma • Hodgkin’s lymphoma • Non-Hodgkin’s lymphoma o Burkitt’s lymphoma o Primary central nervous system lymphoma
- Extreme tonsillar enlargement – upper airway obstruction
- Splenic rupture
- Haemolytic anaemia, thrombocytopenia
Define anaphylaxis
Rapidly developing airway +/or breathing +/or circulation problems usually associated with skin + mucosal changes
Acute onset
Most involve IgE
>2 organ systems are affected [most often skin + resp system]
Although skin + mucosal changes can be dramatic + uncomfortable, without ABC problems isolated skin changes do not indicate anaphylaxis
Aspirin overdose
Normal tablets?
Overdose?
Severe/fatal toxicity?
Usually 300 mg tablets
> 150mg/kg body weight/ >6.5g – overdose
> 500mg/kg body weight – severe/fatal toxicity
Paracetamol overdose
Normal tablets?
Overdose?
Severe/fatal toxicity?
Usually 500mg tablets
Recommended dose of paracetamol – 4g or 75mg/kg in 24h for an adult patient
Single acute overdose – ingestion of >4g or >75 mg/kg in a period <1h
Staggered overdose – ingestion of multiple doses of paracetamol over a period of >1h exceeding recommended dosage
Paracetamol can cause serious fatal effects at around 150mg/kg for many adults
Pathophysiology of paracetamol overdose + treatment
Overdose - liver can’t metabolise it - paracetamol metabolised via an alternative pathway by CYP450 - toxic metabolite produced (N-acetyl-p-benzoquinone imine (NAPQI) - inactivated by glutathione to prevent harm
Depleted glutathione stores - NAPQI accumulates, reacts with cells leading to necrosis
Necrosis occurs in the liver + kidney tubules
IV acetylcysteine
Indication for platelet transfusion
Active bleeding + platelets <50*109/L
or bone marrow failure + platelets <10*109/L
(normal platelet count 150-450*109/L)
What is Actinic keratosis + Bowen’s disease?
• Actinic keratosis – precancerous lesion that can turn into squamous cell carcinoma
• Bowen’s disease/squamous cell carcinoma in situ - early stage of the squamous cell carcinoma
o Tumour can be found in the epidermis but it hasn’t broken through the basement membrane
o Atypical, large, over-pigmented cells
4 subtypes of BCC
- Nodular [most common]
- Superficial [flat shape]
- Morpheic [yellow waxy plaque, scar like]
- Pigemented [dense colour, specks of colour]
https://image.slidesharecdn.com/bcc-100906062810-phpapp02/95/basal-cell-carcinoma-9-728.jpg?cb=1283754650
4 subtypes of malignant melanoma
- Superficial spreading [most common]
- nodular [domed shape, rapid growth]
- lentigo maligna [flat lesions often on face, elderly]
- acral lentiginous [palms, soles, nail beds, often in non-caucasians]
Skin cancer referrals
Referral
• Melanoma – urgent referral
• SCC – urgent referral
• BCC – routine referral
What are melanocytic lesions?
• Melanocytic lesions = not cancer, benign neoplasms of melanocytes in epidermis
What type of hypersensitivity reaction is atopic eczema?
Type I hypersensitivity (IgE mediated)
What type of hypersensitivity reaction is contact dermatitis?
Type IV hypersensitivity (delayed)