Infectious diseases 1 Flashcards
(77 cards)
1
Q
What is the transmission route of HSV-1
A
Respiratory, saliva
2
Q
What is the transmission route of HSV-2
A
Sexual contact, perinatal
3
Q
What is the transmission route of VZV
A
Respiratory
4
Q
What is the transmission route of EBV
A
Saliva - ‘kissing disease’
5
Q
What is the transmission route of CMV
A
Congenital, sexual, saliva
6
Q
What is the transmission route of HHV-6
A
Saliva
7
Q
What is the transmission route of HHV-7
A
Saliva
8
Q
What is the transmission route of HHV-8
A
Sexual contact
9
Q
Presentation of HSV-1 (5)
A
Gingivostomatitis, keratoconjuctivits, herpes labialis, Temporal lobe encephalitis, eczema herpeticum
10
Q
Presentation of HSV-2
A
Genital herpes, Neonatal herpes
11
Q
Presentation of VZV
A
Chicken pox, shingles
12
Q
Presentation of EBV
A
Mononucleosis (associated with lymphomas, nasopharyngeal carcinoma)
13
Q
Presentation of CMV (5)
A
retinitis, hepatitis, colitis, pneumonia, or encephalitis in the immunocompromised
14
Q
Presentation of HHV6
A
Roseola Infantum
15
Q
Presentation of HHV7
A
Roseola Infantum
16
Q
Presentation of HHV8
A
Kaposi sarcoma (Immunocompromised patients)
17
Q
What is infectious mononucleosis associated with
A
lymphomas, nasopharyngeal carcinoma
18
Q
What pathogen causes gingivostomatitis
A
HSV1
19
Q
What pathogen causes keratoconjunctivitis
A
HSV1
20
Q
What pathogen causes herpes labialis
A
HSV1
21
Q
What pathogen causes temporal lobe encephalitis
A
HSV1
22
Q
What pathogen causes genital herpes
A
HSV2
23
Q
What pathogen causes neonatal herpes
A
HSV2
24
Q
What pathogen causes chicken pox
A
VZV
25
What pathogen causes shingles
VZV
26
What pathogen causes infectious mononucleosis
EBV
27
What pathogen causes roseola infantum
HHV6 and HHV7
28
What pathogen causes Kaposi's sarcoma
HHV8
29
Symptoms of HSV2
```
Genital herpes (Chronic-life long)
flu-like prodrome
vesicles/papules around genitals, anus
Shallow ulcers
Urethral discharge
Dysuria
Fever and malaise
```
30
Mx of HSV1
Topical, oral or IV acyclovir
31
Peak age on chickenpox
4-10 years
32
Shingles peak age
over 50
33
Presentation of varicella 3, describe the rash 2 and where
Prodromal malaise
Mild pyrexia
Generalised pruritic, vesicular rash - face and trunk predominantly
34
Presentation of varicella zoster and time line
May occur due to stress
Tingling in a dermatomal distribution on one side of the body
Followed by painful skin lesions.
Recovery in 10–14 days.
35
How long is recovery of varicella zoster
10-14 days
36
Mx of varicella in children (3)
Treat symptoms
Calamine lotion
Analgesia
Antihistamines
37
Mx of varicella in adults
Consider aciclovir, valaciclovir or famciclovir if within 24 h of rash onset
38
Mx of varicella zoster in adults (1st, 2nd line)
1st line: Valaciclovir or famciclovir
2nd line: Aciclovir
if within 72 h of appearance of the rash for 7 days
39
In who is prevention of varicella zoster indicated (2)
immunosuppressed
| Pregnant women exposed to varicella zoster
40
Presentation of EBV (4)
Fever
Hepatosplenomegaly (jaundice)
Pharyngitis (Tonsillar Exudates)
Lymphadenopathy (Posterior Cervical Nodes)
41
Triad of infectious mononucleosis
Fever
Lymph adenopathy
Pharyngitis
42
What is the pathophysiology behind EBV infection
EB infects epithelium of throat and causes pharyngitis
Virions enter lymph vessels and travel to lymph nodes where they attach to B lymphocytes and infect them.
These actively replicate and produce heterophiles antibody.
Activated T cells kill productive B cells.
Latent infected B cells are lifelong.
43
Ix for mononucleosis (5)
```
FBC - Lymphocytosis (highest in week 2-3)
Blood film - Atypical lymphocytosis
Heterophile antibodies - Monospot test
EBV specific antibodies
Real time PCR - EBV DNA detection
```
44
Mx for mononucleosis (3)
Supportive care - Paracetamol or Ibuprofen (anti inflammatory + analgesics)
Corticosteroids may be indicated for severe cases (e.g. haemolytic anaemia, severe tonsillar swelling, obstructive pharyngitis).
Amoxicillin or ampicillin is CONTRAINDICATED due to widespread maculopapular rash
45
Prognosis of mononucleosis
Recovery in 3-21 days
46
A 32 year old librarian presents to GP with a history of sharp tingling around his lips followed by a painful ulcer on the side of his mouth. O/E he has cervical lymphadenopathy and a blister on his finger. What is the pathogen and what is on his finger?
HSV1 and herpetic whitlow
47
A 6-year old girl presents with a fever of 38.5, fatigue and a itchy, maculopapular rash on her face and trunk. Other children at school present with similar symptoms. How should this patient be managed?
Paracetamol with calamine lotion
48
A wild medical student presents with sore throat and tonsillar exudates, posterior cervical lymphadenopathy and his basic observations are 38.9oC, HR is 90bpm and oxygen saturation on air is 99%. On examination there is splenomegaly. His condition is most likely due to which pathogen?
EBV
49
A 42-year-old man, previously treated for pneumocystic pneumonia and oral ulcers, presents with a purple, purpural lesion on his nose. Which is the causative organism for this skin lesion?
HSV8
50
What is pathogenesis of HIV
1. HIV enters the CD4 lymphocytes following binding of its envelope glycoprotein (gp120) to CD4 and a chemokine receptor.
2. Reverse transcriptase (in viral core) reads RNA to manufacture DNA
3. Viral DNA is incorporated into the host genome.
4. Dissemination of virions leads to cell death
5. Eventually to T-cell depletion.
51
Ways of HIV transmission
```
Sex
Pregnancy/childbirth/breast feeding
Injection drug use
Occupational exposure
Blood transfusion or organ transplant
```
52
4 stages of HIV
Flu-like
Feeling fine
Falling count
Final crisis
53
What EBV mediated pathology occurs in HIV patients and organ transplant patient
Hairy leukoplakia
54
What are hairy leukoplakia
Irregular, white, painless plaques on lateral tongue that cannot be scraped off.
EBV mediated.
Occurs in HIV-positive patients, organ transplant recipients.
55
What does Candida albicans cause
Thrush
56
What are risk factors to oral candidiasis and oesophageal thrush
Immunocompromisation
57
What are RF of vulvovaginitis
Diabetes, use of antibiotics
58
What conditions can candidiasis cause
```
Oral candidiasis
Oesophageal thrush
Vulvovaginitis
Diaper rash
Infective endocarditis
Disseminated candidiasis
```
59
Which patients are particularly susceptible to disseminated candidiasis
Neutropenic patients
60
S/s of oral candidiasis and oesophageal thrush
Dysphagia
61
S/s of Vulvovaginitis/ Balanitis
Thick discharge, itching, soreness, redness
62
S/s Disseminated candidiasis (3)
Fever, hypotension +/- leucocytosis
63
Ix for candidiasis (5)
```
Urinalysis (UTI)
Random or fasting blood glucose (Diabetes)
Glucose tolerance test (Diabetes)
HIV antibody test
Vaginal pH test (to exclude STIs)
```
64
Systemic candidiasis s/s (3)
fever, hypotension +/- leucocytosis
65
Where does candidiasis disseminate to (6)
retina, kidney, liver, spleen, bones, CNS
66
Mx of oral candida (2)
Miconazole oral gel and Nystatin suspension
67
Mx of thrush
Clotrimazole
68
HIV associated tumours (3)
Kaposi's sarcoma
Squamous cell carcinoma
Lymphoma
69
How does Kaposi's sarcoma present and what causes it
may present as a pink or violaceous (purple) patch on the skin or in the mouth.
HHV8
70
Ix for HIV (5)
ELISA, confirmed with Western blot
Serum HIV rapid test
Serum HIV DNA PCR - infants
CD4 count – indicates immune status, assists staging process
Serum viral load (HIV RNA) - millions of copies/mL
71
Centor criteria for tonsillitis (4)
o Tonsillar exudate
o Tender anterior cervical lymphadenopathy or lymphadenitis
o History of fever over 38
o Absence of cough
72
Ix for tonsillitis
Rapid streptococcal antigen test
| Throat culture
73
Viral causes of tonsillitis (3)
rhinovirus, coronavirus, adenovirus
74
Bacterial causes of tonsillitis (3)
Group A streptococci
Mycoplasma pneumoniae,
Neisseria gonorrhoea
75
Which organism usually causes an abscess in the skin
Staph A
76
What group of patients commonly get perianal (2)
IBD and diabetes
77
What are ring-enhancing lesions in a HIV patient suggestive of
Toxoplasma Gondii
