Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Medicine (Year 5) > Infectious diseases (Disease summaries) > Flashcards

Infectious diseases (Disease summaries) Flashcards

1
Q

types of malaria

A

Most common tropical disease in the UK
* 75% falciparum (90% of cases from Africa)
* 25% Ovale (90% of cases from India)

Initially ALWAYS TREAT AS FACIPARUM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

5 species of malaria

A

Plasmodium:

  • falciparum
  • Vivax
  • Ovale
  • Malaria

Vector: female anopheles mosquito

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

course of illness: malaria

A

Incubation period: Minimum 7 days

  • Most cases of falciparum malaria present within 2-3 months and nearly all within 6 months
  • Non-falciparum malaria may present after months-years due to the reactivation of hypnozoites- Vivax/ ovale up to a year (lay dormant in the liver)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

pathophysiology behind malaria

A
  1. Sporozoites are transmitted by Anopheles mosquito bites and travel through the blood to hepatocytes, where they mature into schizonts and release merozoites into the bloodstream.
  2. The merozoites invade red blood cells, mature into schizonts and rupture to release merozoites and the cycle repeats.
  3. Plasmodium vivax and Plasmodium ovale can remain dormant for months in the liver by producing hypnozoites which can lead to relapses after the initial infection.
  4. Plasmodium falciparum does not produce hypnozoites and is not associated with relapse.
  5. Plasmodium malariae also does not produce hypnozoites but can persist in the blood for years.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

presentations of malaria

A

often non-speciifc symptoms with a history of travel to endemic area and fever

  • high fever, sweats and rigors
  • headache, myalgia, arthralgia
  • lethargy
  • reduced appetite, nausea, jaundice, abdominal pain
  • hepatomegaly and splenomegaly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

presentation of faliciparum malaria

A

Falciparum malaria is the most severe type of malaria. Features include suggesting severe malaria include:

  • Cerebral involvement – reduced consciousness, seizures
  • Renal impairment – oliguria
  • Acidosis – may cause deep breathing
  • Hypoglycaemia – more common in pregnant people
  • Respiratory distress – pulmonary oedema or acute respiratory distress syndrome (ARDS) – more common in pregnant people
  • Severe anaemia
  • Haemorrhage – specifically disseminated intravascular coagulopathy
  • Shock
  • Sepsis – more common in pregnant people
  • Haemoglobinuria – falciparum malaria can cause severe haemolysis and dark red urine (also known as ‘blackwater fever’)
  • Parasitaemia (>10%.)
  • Schizonts on a blood film
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

pesentation of Non-falciparum malaria

A

Plasmodium vivax is them most common cause of non-falciparum malaria. Features of non-falciparum malaria include:

  • The general features of malaria discussed above
  • Cyclical fever – paroxysms of fever based on the parasite’s lifecycle:
  • Plasmodium vivax and Plasmodium ovale – every 48 hours
  • Plasmodium malariae – every 72 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

investigations for malaria

A

Blood film- gold standard

  • x 3 blood films

Bloods (FBC, UE, LFT, glucose, coagulation)

  • anaemia
  • thrombocytopenia
  • leukopenia
  • abnormal liver test- unconjugated bilirubin
  • blood glucose - hypoglycaemia

Imaging- cT

  • if symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

management of: non-falciparum malaria

A

oral artemisinin combination therapy (ACT)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

management of: uncomplicated Falciparum

A

admit all patients with falciparum

  • artemisinin combination therapy (ACT)
  • or quinine with doxycyline
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

management of: complicated Falciparum

A

admit

  • IV artesunate
  • or intravenous quinine (need to monitor for hypoglycaemia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

preventing malaria

A

General advice for preventing malaria when travelling to endemic areas:

  • No method is 100% effective alone
  • Use mosquito spray (e.g., 50% DEET spray)
  • Use mosquito nets and barriers in sleeping areas
  • Seek medical advice if symptoms develop
  • Take antimalarial medication as recommended

Antimalarial medications are not 100% effective. The main options are:

  • Proguanil with atovaquone (Malarone)
  • Doxycycline
  • Mefloquine (risk of psychiatric side effects)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Proguanil / atovaquone (Malarone)

A

is slightly more expensive than the other options but has the least side effects. It is taken from two days before until seven days after travel to an endemic area.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Doxycycline

A

is a broad-spectrum antibiotic that can cause side effects such as diarrhoea and thrush. It also causes skin sensitivity to sunlight, increasing the risk of sunburn and skin reactions. It is taken two days before until four weeks after travel to an endemic area.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Dengue fever

A

found in Africa, Asia, India and S and C America
- Arbovirus
- Vector : mosquito

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Course of illness: Dengue fever

A

1) First infection ranges from asymptomatic to non-specific febrile illness (classic dengue)

  • Lasts 1-5 days
  • Improves 3-4 days after rash
  • Supportive treatment only

2) Re-infection with different serotype is very dangerous

  • Antibody dependent enhancement (immune system overdrive)
  • Dengue haemorrhagic fever (children)
  • Dengue shock syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

presentation of Dengue fever

A
  • a high temperature, or feeling hot or shivery.
  • a severe headache.
  • thrombocytopenia and haemorrhage
  • pain behind the eyes
  • muscle and joint pain.
  • feeling or being sick.
  • a widespread red rash.
  • tummy pain and loss of appetite.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

investigations for dengue

A
  • PCR
  • Serology e.g. IgM and IgG
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

management of dengue fever

A

NO SPECIFIC TREATMENT

  • paracetamol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

prevention of dengue

A

Vaccine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

severe dengue

A

Severe dengue is a more virulent form which can cause:

  • Disseminated intravascular coagulopathy
  • Shock – known as dengue shock syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

typhoid fever

A
  • also known as ‘enteric fever’
  • associated with poor sanitation- Asia, Africa and S America

Pathogen: Salmonella typhi and Salmonella parathyphi (Paratyphoid)

  • gram negative bacilli
  • faecal oral route
  • fimbriae adhere to ileal lymphoid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Paratyphoid

A

is similar to typhoid fever, but less severe and is caused by Salmonella paratyphi. Both species are spread via the faecal-oral route through contaminated food and water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

course of illness: typhoid

A

Incubation period: 7-14 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

presentation of typhoid

A
  • Initially systemic upset – fever, headaches, malaise, nausea, anorexia
  • Relative bradycardia (sphygmothermic dissociation or Faget sign)
  • Gastrointestinal symptoms – typically pain and constipation (although Salmonella gastroenteritis can cause diarrhoea, enteric fever is associated with constipation)
  • Rose spots – these are small red macules on the skin of the trunk due to bacterial skin emboli
  • Since it can infiltrate the bone marrow, osteomyelitis can occur, especially in people with sickle cell disease.

Other features can include dehydration, peritonitis, pneumonia, encephalitis, pericarditis, and metastatic abscesses (including the liver, spleen, and heart).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

typhoid and relative bradycardia

A

Also known as sphygmothermic dissociation or the Faget sign, this describes fever and bradycardia/unusually low tachycardia, which is the opposite of what is expected (i.e. fever and tachycardia). This sign is associated with intracellular parasites and viral haemorrhagic fever such as typhoid fever, yellow fever, Legionella infection, Q fever, and dengue fever.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

investigations for typhoid

A

Blood, urine and stool culture x 2

  • Blood (+ve in 40-80%)

FBC

  • Moderate anaemia
  • Relative lymphopenia, raise CRP
  • Raised LFTs (transaminase and bilirubin)

No serological test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

management of typhoid

A

Ceftriaxone (resistant starting- having to use meropenem)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

prevention of typhoid

A
  • Vaccine
  • Eating and drinking
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Non-typhoidal salmonella infections

A
  • Food poisoning salmonellas
  • Widespread distribution including UK e.g. S. typhimurium, S enteridis

Symptoms

  • Diarrhoea
  • Fever
  • Vomiting
  • Abdominal pain

Management

  • Generally self limiting but bacteraemia and deep-seated infections may occur in the immunosuppressed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

other bacterial causes of gastroenteritis

A
  • Norovirus
  • Campylobacter
  • E.coli
  • Clostridium difficile
  • Shigella
  • Bacillus cereus
  • Cholera
  • Cryptosporidiosis
  • Amoebiasis
  • Giardiasis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Campylobacter species:

A
  • The most common bacterial infection of the intestines in the UK
  • Associated with contaminated food, especially undercooked poultry
  • Features: flu-like prodrome (e.g. fever, malaise, myalgia) followed by diarrhoea that may be bloody, abdominal cramps, nausea, and vomiting.
  • Usually self-limiting within 2-3 days and resolves within 7 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Escherichia coli:

A
  • Commonly associated with foreign travel
  • Transmitted through contaminated food via the faecal-oral route
  • Features: watery stools, abdominal cramps, nausea
  • Certain strains can cause haemolytic uraemic syndrome
  • Usually self-limiting and resolves within 10 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Bacillus cereus:

A
  • Transmitted through contaminated food that has been undercooked, classically undercooked reheated rice
  • Features either acute vomiting within ~6 hours (emetic syndrome) or diarrhoea within ~6 hours (diarrhoeal syndrome) however they can overlap
  • Usually self-limiting and resolves within a day
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Clostridioides difficile:

A
  • Usually caused by recent broad-spectrum antibiotic use, most commonly due to cephalosporins, but also clindamycin
  • Features: diarrhoea, abdominal pain, pseudomembranous colitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Shigella:

A
  • Transmitted via the faecal-oral route, often from person-to-person and usually seen in young children (<5 years old)
  • features: bloody diarrhoea and mucus, along with fever, abdominal cramps, and may have nausea and vomiting.
  • Usually resolvers within 7 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Cholera:

A

Vibrio cholerae

  • Associated with poverty and may be seen in returning travellers, particularly drinking untreated water, eating contaminated food, or unsanitary living conditions
  • Features: profuse, watery diarrhoea (‘rice water’ stools that are greyish, cloudy, with mucus) – litres are often lost causing severe dehydration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Cryptosporidiosis:

A
  • The most common protozoal intestinal infection in the UK and associated with foreign travel, transmitted via contaminated food/water
  • Features: watery diarrhoea, abdominal cramps, nausea, vomiting, and fever
  • Symptoms usually last 1-2 weeks
40
Q

investigating for cyptosporidiasis

A

stool: modified Ziehl-Neelsen stain (acid-fast stain) of the stool may reveal the characteristic red cysts

41
Q

management of cryotosporidiasis

A
  • is largely supportive for immunocompetent patients
  • if the patient has HIV and is not on antiretroviral therapy then this should be started and often will be enough to resolve the infection
  • nitazoxanide may be used for immunocompromised patients
  • rifaximin is also sometimes used for immunocompromised patients/patients with severe disease
42
Q

Entamoeba histolytica (amoebiasis)

A
  • Transmitted via the faecal-oral route, usually seen in foreign travel, and has a long incubation period (>1 week)
  • Features: can cause amoebic dysentery (bloody diarrhoea and fever) and possibly an amoebic liver abscess (right upper quadrant pain, constitutional symptoms, and hepatomegaly)
43
Q

investigations: amoebiasis

A
  • Stool OCP (Ova Cyst Parasite)
  • Not shed constantly, need x 3 stools
  • Usually absent with invasive disease
  • Amoebic serology, stool PCR
44
Q

Management: amoebiasis

A
  • IV ceftriaxone (gram positive and negative)
  • PO metronidazole (anaerobic infections and amoebic)
  • US guided hepatic train
45
Q

Giardiasis:

A
  • Transmitted via the faecal-oral route and has a long incubation period (>1 week)
  • Features: chronic non-bloody diarrhoea that is initially watery but can lead to steatorrhoea over time, malabsorption, weight loss, and lactose intolerance
  • Giardiasis should be considered in someone with chronic diarrhoea associated with malabsorption and weight loss.
46
Q

Tuberculosis

A

Tuberculosis (TB) is an infection caused by Mycobacterium tuberculosis. It is spread through inhaling respiratory droplets. TB is a notifiable disease.

Active tuberculosis – when evidence of symptomatic/progressive disease of the lung and/or other organs. If untreated, one person with active pulmonary TB can spread the infection.

Latent TB – a persistent immune response to TB antigens without clinical evidence of active TB. The person is asymptomatic but not infectious. It may reactivate, and cause active TB.

47
Q

demographic affected: TB

A
  • Endemic in parts of Asia, Africa, SA and eastern Europe and was common in the UK until the 1950s (when isoniazid was first developed)
  • Common for people immigrating to the UK for endemic areas to experience reactivation of latent TB after their arrival (maybe Vitamin D deficiency)
48
Q

pathogen: TB

A

Mycobacterium tuberculosis
(acid fast stain)

49
Q

Course of illness: TB

A
  • Transmitted by aerosol inhalation and causes pulmonary infection, then spreads via haematogenous spread to any site in the body
  • Initial infection can be asymptomatic and then lie dormant (Latent TB) for many years before reactivating later in life to the active infection
  • Reactivation risk (10-15%) due to immunosuppression, advancing age or HIV)
50
Q

Primary tuberculosis

A

Upon entering the lungs, Mycobacterium tuberculosis infects the lungs and can proliferate within alveolar macrophages, resulting in tubercle-laden macrophages known as a Ghon focus.

These combined with hilar lymph nodes form Ghon complexes.

In immunocompetent people, the initial lesion heals by fibrosis. However, those who are immunocompromised may develop disseminated TB.

51
Q

Secondary tuberculosis

A

If the person becomes immunocompromised (e.g. HIV), the infection can reactivate, which often happens in the lung apex and can spread. The most common area of secondary infection is the lungs. If bacteraemia occurs in primary/secondary infection, then deposits of bacteria can occur in different organs, which can also reactivate, resulting in disseminated infections.

Sites that may be affected include spinal TB (osteomyelitis), TB meningitis, TB pericarditis, and abdominal TB.

52
Q

Active extrapulmonary TB

A

symptoms that are seen in regions outside of the lungs, including the meninges, lymph nodes, bones and joints, heart, eyes, and gastrointestinal system etc.

53
Q

Disseminated (miliary) TB

A

when ≥2 organ systems are affected which is more common in children and immunocompromised people, however, it can occur in the absence of immunodeficiency.

54
Q

Multidrug-resistant TB

A

a strain of TB that is resistant to two first-line drugs. Taking the wrong dose or combination, or irregularly can increase the risk of this. Extensively drug-resistant TB may occur if further resistance occurs.

55
Q

risk factors for TB

A
  • Living in an endemic area (e.g. Asia, Africa, Eastern Europe, Latin America)
  • Exposure to a person infected with TB
  • HIV – the risk of developing active TB is 20-30 times more likely
  • Immunocompromised states – including immunosuppressive treatment and diabetes mellitus
  • Lung fibrosis – including silicosis and apical fibrosis
  • Young children – are more likely to develop severe disease
  • Poverty and deprivation – including hostels, shelters, prisons etc.
  • Alcohol
  • Intravenous drug use
  • Smoking
56
Q

Features of active tuberculosis include:

A

Constitutional symptoms

  • fever
  • weight loss
  • drenching night sweats
  • malaise
  • anorexia

Pulmonary symptoms

  • cough
  • sputum
  • dyspnoea
  • haemoptysis (a late sign)
57
Q

signs of TB

A
  • Clubbing
  • Cachexia
  • Lymphadenopathy
  • Hepato/splenomegaly
  • Erythema nodosum
  • Crepitation or bronchial breathing if PE
58
Q

Features of extrapulmonary tuberculosis include:

A
  • Skin involvement – erythema nodosum (occurs due to a TB hypersensitivity reaction), lupus vulgaris (painful nodular lesions on the face)
  • Lymphadenopathy – often painless, rubbery, and in the supraclavicular and cervical regions
  • Neurological involvement – headache, vomiting, confusion, cranial nerve palsy
  • Skeletal/joint involvement – bone/joint pain, joint swelling, back pain
  • Abdominal involvement – abdominal/pelvic pain, constipation, bowel obstruction
  • Urinary involvement – dysuria, polyuria, haematuria
59
Q

investigations for TB

A

Chest X-ray:

  • may show hilar lymphadenopathy, cavitation, and pleural effusion
  • Upper lobe cavitation can suggest reactivated TB
  • Features tend to affect the upper lobes

Sputum smear – should be done with 3 specimens:

  • The sample is stained with the Ziehl-Neelsen stain for acid-fast bacilli
  • This is non-specific as it will stain positive for all Mycobacteria species

Nucleic acid amplification tests (NAAT):

  • Allows quicker diagnosis within 48 hours, but is less sensitive than culturing

Sputum culture – the gold-standard test:

  • This also can assess drug sensitivities, however, takes 1-3 weeks

HIV testing

– should be offered to all people with TB: HIV can alter the treatment of TB and may be the cause of its reactivation

60
Q

Screening for TB

A

Screening tests may identify latent TB, however, their results depend on the person’s immune status, history of TB exposure, and whether they have had the Bacillus Calmette-Guérin (BCG) vaccination. They can include:

  • Mantoux test – tuberculin is injected intradermally: Skin induration >5 mm represents a positive result
  • Interferon-gamma release assay (IGRA) – testing white blood cells’ response to TB antigens: This is faster and less likely to give a false positive result
61
Q

If a test for latent TB infection is positive..

A
  • The person should be assessed for TB e.g. CXR
  • If there is no evidence of active infection, then the person should be treated for latent TB to prevent progression to active disease.
62
Q

management: latent TB

A
  • 3 months of rifampicin and isoniazid
  • or 6 months rifampicin alone
    • pyridoxine

Treatment reducing risk of reactivation needs to be balanced against hepatotoxicity risk (>35 yo at high risk)
- monitor LFTs before and after

63
Q

management of active TB

A
  • Rifampicin for 6 months
  • Isoniazid for 6 months
  • Pyrazinamide for 2 months
  • Ethambutol for 2 months

+ pyridoxine

Monitor LFTs before and after treatment- if LFTS deranged treatment can either be stopped and drugs gradually reintroduced once they have normalised

64
Q

side effects of RIPE

A

Rifampicin

  • red secretions
  • hepatotoxicity

Isoniazid

  • Peripheral neuropathy – pyridoxine (vitamin B6) is co-prescribed to prevent this
  • hepatotoxicity

Pyrazinamide

  • Photosensitivity
  • Arthralgia
  • hepatotoxicity

Ethambutol

  • Optic neuritis – visual acuity is checked before and during treatment
  • Nephrotoxicity
65
Q

Disseminated/ Miliary TB

A
  • Characteristic appearance on CXR/CT- widespread throughout patient (CNS/ bone marrow/ pericardium)
  • Requires neuroimaging and lumbar puncture to exclude CNS involvement
  • Treatment for miliary TB shouldn’t be delayed whilst awaiting biopsies
66
Q

TB contact tracing

A
  • Once a patient has been diagnosed they should be referred to the TB nurses
  • They will perform contact tracing and will test household contacts with either CXR or QuantiFERON testing and will treat any latent TB
  • Usually if household contacts were going to catch TB it would be before the patient was admitted so visitors are allowed – unless they have resistant TB
67
Q

TB infection control

A
  • Patients with non-resistant pulmonary TB should be nursed in a side room.
  • After 2 weeks of treatment patients are generally considered non-infectious to immunocompetent individuals.
  • If the ward also manages immunocompromised patients, including HIV (i.e our ward!) then patients with respiratory TB need to be nursed in a side room until discharge regardless of whether they are smear positive or negative (there are criteria by which they can come out but they are very stringent)
  • Smear positive patients can still be discharged home but would need to quarantine themselves at home until they have completed 2 weeks of treatment.
  • NICE guidance is that staff do NOT need to wear masks/aprons unless MDR TB is suspected or they are performing an aerosol generating procedure such as giving a nebuliser.
  • Patients with smear positive TB DO need to wear a mask when leaving their room until they have completed 2 weeks of treatment.
68
Q

HIV

A

Retrovirus ssRNA

MOA: By infecting and destroying CD4+ T-cells, HIV causes immunodeficiency.

Transmission is via blood, blood products, sexual fluids, and breastmilk and may occur via:

  • Sexual transmission (e.g. unprotected sexual transmission)
  • Pregnancy (e.g. during delivery, breastfeeding)
  • Blood transfusion – blood is screened for HIV to reduce the risk
  • Intravenous drug use and sharing needles
  • Occupational exposure – such as needlestick injuries
69
Q

course of illness: HIV

A

* Stage 1: Acute HIV infection (2-4 weeks after infection) – flu like illness- seroconversion
* Stage 2: Clinical latency/ chronic HIV infection- usually symptomless (some people without HIV treatment can 10-15 years without symptoms
* Stage 3: AIDS

70
Q

Advanced HIV disease (also known as AIDS).

A
  • Advanced HIV disease (or AIDS) occurs when CD4+ cell counts are very low (<200 cells/mm3) and opportunistic infections or malignancies develop. These conditions are known as AIDS-defining illnesses.
71
Q

risk factors for HIV

A
  • Unprotected anal or vaginal sex
  • Multiple sexual partners
  • High-risk sexual practices (e.g. chemsex)
  • Other sexually transmitted infections (STIs) including syphilis, Chlamydia, gonorrhoea, and herpes
  • Sex work
  • Sharing contaminated needles and intravenous drug use
  • Injections, transfusions, procedures involving unsterile cutting/piercing without HIV screening
  • Accidental needlestick injuries and occupational exposure
  • Living in an area with high HIV prevalence
72
Q

Presentation of HIV

A
  • Patients with HIV may present with infections not commonly seen in the general population.
  • Flu like symptoms (fever, chills, rash, night sweats, muscle aches, sore throat, fatigue, swollen lymph nodes, mouth ulcers)

AIDs

  • Rapid weight loss
  • Recurring fever
  • Extreme and unexplained tiredness
  • Swelling of lymph glands in armpits, groin or neck
  • Diarrhea that lasts for more than a week
  • Sore of the mouth, anus, or genitals
  • Pneumonia
  • Memory loss, depression…
73
Q

HIV: Associated Respiratory Conditions

A

Pneumocystis pneumonia (PCP)

TB

74
Q

TB

A

Tuberculosis

Tuberculosis is a common presenting condition in HIV and can be pulmonary or extrapulmonary. People may present with constitutional symptoms and cough.

75
Q

Pneumocystis pneumonia (PCP)

A

Previously known as Pneumocystis carinii, Pneumocystis jirovecii is a fungus that can cause pneumocystis pneumonia (PCP), an opportunistic infection in people with HIV. PCP is the most common AIDS-defining illness and is often seen when the CD4+ count is <200 cells/mm3.

PCP can be life-threatening and difficult to diagnose as it is insidious and develops over weeks.

76
Q

HIV associated neurological conditions

A

Cerebral toxoplasmosis
Cytomegalovirus
Encephalitis
Cryptococcus
AIDs dementia complex

77
Q

HIV renal related conditions

A

HIV-associated nephropathy- nephrotic syndrome

78
Q

HIV: Associated Malignant Conditions

A

Kaposi’s sarcoma
Lymphoma
Cervical cancer

79
Q

HIV: Associated Skin Conditions

A

As well as Kaposi’s sarcoma, HIV is associated with skin conditions that are unusually severe, recurrent, or resistant to treatment including:

  • Fungal infections of the skin and nails (e.g. pityriasis versicolor)
  • Bacterial infections – such as impetigo or folliculitis
  • Herpes simplex – particularly if ulcers are unusually large/persistent
  • Shingles – especially if more than 1 dermatome is affected
  • Seborrhoeic dermatitis and psoriasis
  • Molluscum contagiosum
  • Warts
80
Q

HIV: Associated Oral Conditions

A

Oropharyngeal candidiasis

Oral hairy leukoplakia

Gingivitis

Apthous ulcers

81
Q

Oral hairy leukoplakia

A

Oral hairy leukoplakia is associated with the Epstein-Barr virus and is nearly exclusively seen in people with HIV. This presents with a white patch that is corrugated/hairy on the tongue and occurs due to epithelial hyperplasia of the oral mucosa.

82
Q

HIV and CD4 Counts

A

Different opportunistic infections and AIDS-defining illnesses can occur according to the CD4 count. In general:

  • CD4+ 200-500 cells/mm3: oral candidiasis, shingles, Kaposi’s sarcoma, oral hairy leukoplakia
  • CD4+ 100-200 cells/mm3: Cerebral toxoplasmosis, PML, PCP, AIDS dementia complex, Cryptosporidium infection
  • CD4+ 50-100 cells/mm3: oesophageal candidiasis, cryptococcal meningitis, primary cerebral lymphoma, aspergillosis
  • CD4+ <50 cells/mm3: CMV infection, Mycobacterium avium cellulare infection
83
Q

HIV investigations

A

Combined: P24 and HIV antibody testing are used for the diagnosis and screening of HIV

  • In asymptomatic people, testing should be done at 4 weeks post-exposure:
  • If negative, offer a repeat confirmatory test at 12 weeks
84
Q

HIV antibodies vs P24

A

HIV antibodies

HIV antibodies may not be present in early infection, however, they are present in most people at 4-6 weeks and over 90% at 3 months. They are screened for using an ELISA (Enzyme Linked Immuno-Sorbent Assay) test and a repeat test to confirm is done using an HIV-1/HIV-2 differentiation assay.

p24 antigen

The p24 antigen is a viral protein that can be found earlier as viral RNA rises in the blood. It is usually positive at 1-4 weeks after infection.

85
Q

HIV prophylaxis

A

Post-exposure prophylaxis

Pre-exposure prophylaxis

86
Q

Post-exposure prophylaxis

A
  • If PEP is indicated, then combination antiretroviral therapy is started as soon as possible (ideally within 1-2 hours, but up to 72 hours) for 4 weeks. Combined testing is done at 12 weeks post-PEP.
87
Q

Pre-exposure prophylaxis

A

Pre-exposure prophylaxis (PrEP) may be prescribed in specialist sexual health services to people who are at high risk of HIV transmission including:

HIV-negative men who have condomless sex with other men.
HIV-negative heterosexual men and women having condomless sex with partners who are HIV positive
HIV-negative trans women who are identified as being at elevated risk of HIV acquisition through condomless sex

88
Q

management of HIV

A

The management of HIV involves the use of a combination of antiretroviral drugs.

They are now started as soon as someone is diagnosed with HIV rather than waiting for a CD4+ count of <200 cells/mm3.

89
Q

if CD4 <20

A

should be prescribed Co-trimoxazole 480mg PO OD as primary prophylaxis against PCP.

90
Q

<50 CD4

A

CD4 <50 Azithromycin 1250mg PO once weekly to protect against MAI
Should be assessed by ophthalmology with dilated fundoscopy to look for evidence of intra-ocular infections such as CMV retinitis

91
Q

Yellow fever

A

Yellow fever is a type of zoonotic viral haemorrhagic fever caused by the yellow fever virus, which is transmitted by Aedes mosquitos. If severe enough, it can cause fever, haemolytic jaundice, and acute kidney injury.

Other examples of viral haemorrhagic fever include dengue fever and Ebola.

92
Q

presentation of yellow fever

A
  • Initial 3-4 days of acute fever, headache, malaise, and myalgia followed by a brief remission
  • After a few days, a second episode of high fever occurs, along with nausea, vomiting, abdominal pain, and drowsiness
  • Hepatitis, jaundice, and haemorrhage follow (e.g. haematemesis, melaena, petechiae, purpura, epistaxis)
  • Oliguria and uraemia can develop as acute kidney injury occurs
  • Bradycardia may be seen
93
Q

schistosomiasis

A

Schistosomiasis describes an infection with parasitic worms, more specifically flukes (trematodes), of the Schistosoma genus.

Three clinically-relevant species are:

  • Schistosoma haematobium – infects the bladder, endemic in Africa and the Middle East
  • Schistosoma mansoni – infects the colon and portal system, endemic in Egypt, Africa, the West Indies, and South America
  • Schistosoma japonicum – infects the colon and portal system, endemic in Japan, China, and the Philippines

This section will focus on Schistosoma haematobium as it is a risk factor for bladder cancer.

94
Q

presentation of schistosomiasis

A
  • ‘Swimmers itch’ – an allergic contact dermatitis reaction that occurs in infected skin
  • Characterised by urticaria, pruritus, and papules
  • General features – including fever, diarrhoea, myalgia, arthralgia
  • Urinary symptoms – dysuria and haematuria
95
Q

investigations for schistosomiasis

A
  • Full blood count (FBC) and differential: may show eosinophilia
  • Abdominal X-ray: may show calcified areas representing eggs, not the bladder itself
  • Serum Schistosoma antibodies: often performed in asymptomatic patients
  • Urine or stool microscopy: often performed in symptomatic patients, shows eggs
96
Q

management of schistosomiasis

A

single dose of praziquantel

Medicine (Year 5) (34 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions