Download MBBS (Bachelor of Medicine, Bachelor of Surgery) 1st Year, 2nd Year, 3rd Year and Final year Surgery 60 Tropical Surgery PPT-Powerpoint Presentations and lecture notes
Tropical Surgery:
TB, Amoebiasis, Filariasis,
Typhoid, Ascariasis
Dept Of Surgery
Tuberculosis
M. tuberculosis as causative agent for
tuberculosis
Robert Koch
1886
TB ? A Multi-system Infection
? Extra-pulmonary form of TB account for 10-15
per cent of all cases and up to 50 per cent of
patients with AIDS.
? TB of the gastrointestinal tract is the sixth most
frequent form of extra-pulmonary site, after
lymphatic, genitourinary, bone and joint,
miliary and meningeal tuberculosis.
Pathogenesis
The postulated mechanisms by which the
tubercule bacilli reach the gastrointestinal tract
are:
(i) hematogenous spread from the primary lung focus in
childhood, with later reactivation;
(ii) Ingestion of bacilli in sputum from active pulmonary focus;
(iii) direct spread from adjacent organs;
(iv) through lymph channels from infected nodes.
Pathogenesis
? The most common site of involvement-
ileocaecal region
? Frequency of bowel involvement declines as
one proceeds both proximally and distally
from the ileocaecal region.
Pathology
Most active inflammation in submucosa.
Bacil in depth of mucosal glands
Inflammatory reaction
Phagocytes carry bacil i to Peyers Patches
Formation of tubercle
Tubercles undergo necrosis
Portis (1953)
Pathology
Submucosal tubercles enlarge
Endarteritis & edema
Sloughing
Ulcer formation
Accumulation of col agenous tissue
Thickening & Stenosis
(Howel & Knapton, 1964)
Pathology
Inflammatory process in submucosa penetrates to serosa
Tubercles on serosal surface
Bacil i reach lymphatics
Bacil i via lymphatics
Lymphatic obstruction
Regional lymph nodes
of mesentery and bowel
? Hyperplasia
Thick fixed mass
? Caseation necrosis
? Calcification
(Boyed, 1943)
FORMS OF GI TB
Ulceroconstrictive
Hypertrophic
60% of patients
10% of patients
Highly virulent
Chronic
Mostly smal Intestinal
Mostly Ileocoecal
Mixed 30% of patients
(Howel & Knapton, 1964)
Clinical Features
? acute, chronic or acute on chronic.
? Constitutional symptoms of fever (40-70%), pain (80-
95%), diarrhoea (11-20%), constipation, alternating
constipation and diarrhoea, weight loss (40-90%),
anorexia and malaise.
? Pain-either colicky due to luminal compromise, or
dull and continuous when the mesenteric lymph
nodes are involved.
Diagnosis
Paustian in 1964 stated that one or more of the following four criteria
must be fulfil ed to diagnose abdominal tuberculosis:
(i) Histological evidence of tubercles with caseation necrosis;
(ii) a good typical gross description of operative findings with biopsy of
mesenteric nodes showing histologic evidence of tuberculosis;
(ii ) animal inoculation or culture of suspected tissue resulting in growth
of M. tuberculosis
(iv) histological demonstration of acid fast bacil i in a lesion
Non specific findings include raised ESR, anemia, hypoalbuminemia
? Plain X ray
? Small Bowel Barium Meal
? Barium Enema
? Ultrasonography
? CT Scan
? Colonoscopy
? Laparascopy
? Immunological Tests (value undefined)
? Ascitic Fluid Examination
Management
? Antitubercular therapy
? The recommended surgical procedures today
are conservative:
? Stricturoplasty
? Resection Anastomosis
Amoebiasis
Introduction
? Causative agent: Entamoeba histolytica
? Entamoeba histolytica is the second leading cause of
mortality due to parasitic disease in humans. (The
first being malaria). Amebiasis is the cause of an
estimated 50,000-100,000 deaths each year.
Entamoeba histolytica : life cycle
Clinical manifestations
? Dysentery- principal manifestation
? Appendicitis or amebic ceacal mass
? Amoebic granuloma
? Fibrous stricture
? Intestinal obstruction
? Paracolic abscess, ischiorectal abscess and fistula
Diagnosis
? Sigmoidoscopic examination
? Immunodiagnosis
? Microscopy
? Antigen Detection
? Molecular diagnosis
Amoebicides
Tissue amoebicides
? Metronidazole 500?750 mg three times a day for 5?10 days
? Tinidazole 2g once a day for 3 days is an alternative to metronidazole
Luminal Amoebicides
? Paromomycin 500 mg three times a day for 10 days
? Iodoquinol 650 mg three times a day for 20 days
Surgical Intervention
Filariasis
? MC cause of lymphedema
? Wucheria bancrofti (nematode) in 90% of cases
? Features
Acute
? Fever
? Headache
? Malaise
? Inguinal & axil ary lymphadenitis
? Lymphangitis, Cel ulitis
? Funiculo-epididymo-orchitis
-Chronic
Lymphedema of legs
Hydrocele
Abdominal lymphatic varices
Treatment
? Elevation or periodic compression
? Firm support bandage or compression garment (MLLB)
? Complex decongestive therapy (CDT)
? Massage (MLD)
? Drugs
? Foot and skin hygiene
? Surgery is rarely performed to remove hypertrophied lymph
channels or obstructed lymph channels
Symptomatic and supportive Treatment for other symptoms and signs
Typhoid
Introduction
? Acute enteric infectious disease
? Caused by salmonella typhi (S.Typhi)
? Prolonged fever, relative bradycardia, apathetic facial
expressions,roseola,splenomegaly,hepatomegaly,
leukopenia.
? Intestinal perforation, intestinal hemorrhage
? Antigens: located in the cell capsule
H (flagellar antigen).
O (Somatic or cell wall antigen).
Vi (polysaccharide virulence)
"widal test"
Transmission
? Fecal-oral route
? Close contact with patients or carriers
? Contaminated water and food
? Flies and cockroaches
S.Typhi.
liverspleengall
BM ,ect
2nd bacteremia
early stage&acme stage
(1-3W
stomach
(
Bac. In gall
mononu
clear
phagocy
tes )
Bac. In
Lower
feces
ileum
peyer's patches &
S.Typhi eliminated
mesenteric lymph nodes
convalvescence stage
(4-5w)
LN Proliferate,swel
1st bacteremia
necrosis
defervescence stage
thoracic
(Incubation stage)
Enterorrhagia,i
3-4w
duct
10-14d
ntestinal
perforation
Pathology
? Essential lesion:
Proliferation of RES (reticuloendothelial system )
specific changes in lymphoid tissues & mesenteric lymph
nodes.
"Typhoid nodules"
? Most characteristic lesion:
ulceration of mucous in the region of the peyer's patches
of the small intestine
Complications
? Intestinal hemorrhage
? Intestinal perforation
? Toxic hepatitis
? Acute cholecystitis
? Nephritis
? Hemolytic uremic syndrome.
? Toxic myocarditis
? Bronchitis, bronchopneumonia
? Toxic encephalopathy
? Meningitis
Diagnosis
? white blood cell count is normal or decreased
? Blood culture
? Urine and stool cultures
? Serological tests(Widal test)
Treatment
? Isolation and rest
? Good nursing care and supportive treatment
? Intravenous injection to maintain water and acid-base and
electrolyte balance
? Antibiotics:
? Quinolones
? Chloramphenicol
? Cephalosporines
? Treatment of complications
Ascariasis
Introduction
? a common cream colored roundworm that is
parasitic in the intestines of humans
? Most common helminthic human infection
? Largest nematode to infect the human intestine
? Definitive host : Humans or pigs
Modes of transmission
? Occurs mainly via ingestion of water or food
? Occasionally inhalation of contaminated dust
? Children playing in contaminated soil may acquire the parasite
from their hands
Prior infection does not confer protective immunity
Life Cycle
Symptoms
Symptoms associated with larvae migration
? hemorrhagic/ eosinophilic pneumonia, cough (Loeffler's Syndrome)
? Breathing difficulties and fever
? asthmatic attacks, pulmonary infiltration and urticaria
Symptoms associated with adult parasite in the intestine
? Usual y asymptomatic
? Abdominal discomfort, nausea in mild cases
? Malnutrition in host especial y children in severe cases
? Sometimes fatality may occur when mass of worm blocks the intestine
Diagnosis
? Stool microscopy
? Eosinophilia
? Imaging
? Ultrasound
? Endoscopic Retrograde Cholangiopancreatography
Treatment
? Mebendazole
? Albendazole
? Pyrantel pamoate
? Ivermectin
? Piperazine citrate
? Levamisole
This post was last modified on 08 April 2022