Helicobacter pylori - Portal Neonatal

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Infectious esophagitis
Non-invasive methods to diagnose esophageal
infections without endoscopy are cytology brush
and balloon devices. The latter consists of a tube
with a ridged cytology balloon on the distal end:
when inflated, it can be withdrawn from the
esophagus and the brushings removed and submitted
for cytological evaluation as well as viral
culture. Whereas these methods are useful to identify
Candida, they are less sensitive for viral
disease and have no real advantage over empirical
antifungal therapy. 13
Endoscopy with biopsy is the gold standard for
diagnosing esophageal candidiasis because
mucosal biopsies can be performed. Despite the
fact that gross endoscopic features can suggest a
diagnosis of esophageal candidiasis, this is
confirmed by the presence of hyphae in biopsies.
Cytological specimens, which can be obtained at
the time of endoscopy, are also a sensitive tool for
the diagnosis, especially when organisms are
washed off the tissue surface in mild superficial
candidiasis after processing of bioptic specimens.
When endoscopy is performed in patients with
esophageal candidiasis, removal of plaque material
by scraping with the endoscope is important to
evaluate the underlying mucosa for ulcers. 6 In
general, Candida should not be considered a cause
of esophageal ulcers in HIV-infected patients.
Both oral and intravenous drugs are available for
treating esophageal candidiasis. Oral medications
are generally administered first, whereas intravenous
therapy is reserved for refractory cases or
when oral administration is contraindicated. Nonsystemic
locally acting agents such as nystatin or
clotrimazole are not very effective and must be
reserved for the treatment of oropharyngeal
disease. In patients with mild disease, with
minimal or reversible immunodeficiency, a short
course of therapy with a systemically absorbed
agent can be given, whereas in patients with HIV
infection or with transplantation immunodeficiency,
longer courses of azoles are best given.
Patients with granulocytopenia, at risk for
systemic Candida infection, require the use of
systemically acting intravenous agents such as
azoles or amphotericin B. All available oral agents
(ketoconazole, fluconazole and itraconazole) are
efficacious for the treatment of esophageal
candidiasis (Table 3.3). Ketoconazole and itraconazole
should be avoided in patients requiring anti-
acid therapy, as an alkaline pH limits their
bioavailability. Fluconazole appears to be more
efficacious than itraconazole; a poor response to
fluconazole suggests non-compliance, drug resistance
or other causes for esophageal symptoms. 14
Randomized trials suggest that fluconazole is
significantly more effective for the treatment of
esophageal candidiasis in HIV-infected patients
than ketoconazole and itraconazole. 14 Fluconazole
is available in oral and intravenous preparations,
is minimally metabolized, is highly water soluble
and is slightly protein bound. The new oral
suspension formulations of fluconazole and itraconazole
may have superior efficacy over pills due
to an additional local antifungal effect and
improved absorption. 15 The adverse effects of ketoconazole,
fluconazole and itraconazole are dose
dependent and include nausea, hepatotoxicity,
inhibition of steroid production and cyclosporin
metabolism. 16 The latter effect is more pronounced
with ketoconazole. 17 Minor increases in aminotransferases
are commonly found in patients
treated with oral azoles and do not require drug
discontinuation.
Amphotericin B represents the other family of
antifungal agents (polyene antibiotics), which bind
irreversibly to sterol in fungal cell membranes,
causing cell death. This drug has a limited use for
the treatment of esophageal candidiasis, owing to
its severe side-effects (nephro- and hepatotoxicity).
This drug is now available in an oral
formulation. Patients with esophageal candidiasis
that is resistant to treatment with fluconazole or
other azoles can be treated effectively with lower
doses of intravenous amphotericin B.
The prophylaxis of esophageal candidiasis in
malignancy and transplant patients has yielded
controversial results. 18
Viral infections
HSV and CMV are the most common viral agents
involved in infectious esophagitis, although some
cases have been ascribed to HIV infection of the
esophagus. HSV (HSV I or, rarely, HSV II)
esophagitis causes a self-limited disease in normal
subjects, but it can be severe and prolonged in the
compromised patients.