Gastro OI Flashcards
Causes of oropharyngeal infections and oesophagitis
Candidiasis most common
HSV
CMV
TB
Drugs - doxy, nsaids, iron tablets
Treatment of oral/oesophageal candidiasis
Oral - 1-200mg fluconazole a day for 7-14 days
Oesophageal - 200-400mg OD for 14-21 days
What to do if Candida oesophagitis doesn’t improve with empirical therapy?
Endoscopy with swab and or biopsy - cultures and sensitivities
Management of CMV oesophagitis?
Iv ganciclovir 5mg/kg bd for 2-4 weeks or until symptoms have resolved
If able to swallow and absorb then oral valganciclovir can be used instead
Management of HSV oesophagitis?
Iv aciclovir 5-10mg TDD followed by PO valaciclovir 1g bd for a total of 14 days
Prevention of upper GI tract infection
CART is mainstay
Campylobacter treatment
None if CD4 > 200
Azithomycin if < 200
Diagnosis c diff
Molecular test, Eia for toxins a and b, toxigenic culture, colonoscopy, biopsy, CT scan
Management c diff
Stop causative abx
Non severe treated with metronidazole
Severe treated with vancomycin or fidaxomycin
E. coli diagnostic test
Stool culture preferred
EIA for shiga toxin or molecular test
E. coli treatment
Only if CD4 <200
As per local guidelines
Tx salmonella
Only if CD4 <200
Cipro or ceftriaxone as per local guidelines
Shigella treatment
Only if CD4 <200
Cipro or azithromycin as per local guidelines
Most cases of CMV disease occur in people with a prior CMV infection and CD4 count of..
<50
Symptoms of CMV colitis
Weight loss, anorexia, diarrhoea, abdo pain, fatigue
Fevers
What else should you assess if you suspect CMV colitis?
? Oesophagitis
? Retinitis
When should cART be started in CMV colitis?
If retinitis present start 2 weeks after CMV tx due to IRIS risk
If just colitis don’t delay cART. If diarrhoea continues may need TDM if VL not suppressing.
Cmv biopsy findings
Owls eye inclusions
Positive immunohistochemical staining for CMV
Treatment for CMV colitis
Ganciclovir 5mg/kg bd 2-4 weeks/until symptom resolution
Oral valgancyclovir may be used in less severe disease
Rotavirus, norovirus, astrovirus, coronavirus treatment
Supportive measures
Adenovirus diarrhoea management
Cidofovir iv if clinically significant infection (rare)
CMV prophylaxis
Only for retinitis
Valganciclovir 900mg od until CD4 >100 for 6/12
how is CMV resistance to ganciclovir confirmed?
Detection of mutations in UL97 gene
Resistance to foscarnet or cidofovir occurs through mutations in CMV UL54 gene
Important cART and anti-CMV DDI
Tenofovir and ganciclovir/valganciclovir - renal toxicity
Who is at greatest risk of cryptosporidium?
Those with cd4 <100
Symptoms of cryptosporidiosis
Profuse watery non bloody diarrhoea
Fever and malabsorption common
Nausea vomiting and lower abdo pain may occur
Non bowel issues with cryptosporidiosis occur in which areas?
Pancreatic duct and biliary tree - cholangitis and pancreatitis may occur
Sclerosing cholangitis presents with right upper quadrant pain, vomiting and raised alk phos
How to diagnose cryptosporidiosis?
Microscopy of fresh unconcentrated stool
Repeat samples may be required due to intermittent oocyst secretion
Pcr should be used in addition
Treatment of cryptosporidiosis
Restoration of immune system with cART
Nitazoxanide 500kg bd for 3/7 but may be required for up to 12 weeks
Rehydration, electrolyte replacement, antimotility agents, dietician input
How to prevent cryptosporidiosis
Patients with CD4 <200 should avoid drinking unfiltered water and ensure careful hand hygiene
Bottles water not enough
Specific filtration employing an absolute 1um filter is required - boiling of water should be advocated
Microsporidia presentation
Watery, non bloody diarrhoea with associated malabsorption
Sclerosing cholangitis can occur
Dissemination can lead to encephalitis sinusitis, myosotis and renal and occular infection
How is microsporidia diagnosed?
3 stool samples should be examined with chromotrope and chemofluorescent stains
PCR to aid diagnosis
Small bowel biopsy may be considered if stool samples are consistently negative
Treatment of microsporidia
Early cART
E. Birneusi - oral fumagillin- haematological toxicity
E intestinalis - albendazole
Symptoms of giardia
Chronic diarrhoea. Nausea bloating cramp like abdominal pain indigestion bloating.
Treatment of giardiasis
Metronidazole
Strict hand hygiene
If recurs give metro again, test and treat household contacts
If recurrent in traveller to Asia seek specialist advice
How might amoebiasis present?
Fever, abdo pain, watery or bloody diarrhoea
Can be asymptomatic
Occurs at any cd4 count
Liver abscess can present with fever, RUQ pain and tenderness
How is amoebiasis spread?
Ingestion of cysts in contaminated human faeces
Diagnosis amoebiasis
3 stool samples for cysts and trophozoites PCR method of choice in uk
How is amoebiasis treated?
Metronidazole
Afterwards paromomycin for 5-10 days to eliminate luminal infection
Symptoms of cyclosporiasis
Watery diarrhoea throughout the tropics and subtropics and in returning travellers
Diagnosis of cyclosporiasis
Detection of oocysts in stool
Wet prep
Examination under UB light for parasite autofluorescence or confirmed using modified ZN staining and accurate measurement
PCR can aid and samples should be sent to PHE
Treatment of cyclosporiasis
Cotrimoxazole 960mg BD 7/7
Secondary prophylaxis three times a week may be needed while cART is commenced
How does cystoisoporiasis present?
Chronic diarrhoea sometimes biliary involvement
How is cystoisosporiasis diagnosed?
Oocysts in stool with microscopy with modified ZN staining
How is cystoisosporiasis treated?
Septrin 960mg QDS for 10/7
Secondary prophylaxis 960mg three times a week is essential as relapse is common
What is strongyloides stercoralis?
Gut nematode that causes chronic GI and skin disorders
Autoinfective lifecycle
Can disseminate causing life threatening hyperinfection syndromes in immunosuppressed individuals - corticosteroid use seems to be a causative factor in cases of hyper infection syndrome
Diagnosis strongyloidiasis
Eosinophilia
Larvae in stool specimens
Serology may also be useful but can have cross reaction with other parasitic nematodes
How is strongyloidiasis treated?
Discuss with specialist
Ivermetcin but caution if diagnosed by serology because cross reaction with filaria is possible and encephalopathy can develop
If hyperinfection continue ivermectin for at least 2 weeks
Repeat stool sample at 2-4 weeks to confirm clearance and serology and stool samples every 6-12m for 2yrs after tx
Treatment of schistosomiasis
Praziquantel at dose dependent on species
