Salmonellosis: To Be Forewarned Is To Be Fore-armed

Salmonellosis is an acute infectious disease of human and animals, that is caused by the numerous strains of Salmonella and more frequent courses as gastro-intestinal, rare – as typhoid and septic forms

Etiology: Salmonella, over 2000 strains, Gramm-negative movable bacili, that don't form capsules and spores. Their main antigents are O-H-and Vi, by O-antigen are devided on groups (A, B, C, D, E, F etc.). Most often salmonella infection are called by:

•         S. typhimurium

•         S. enteritidis

•         S. java

•         S. anatum and other

Bacteria are stable in the environment (for months and years they live in food, water, soil), hot temperature kill them in 1 hour.

Epidemiology:

·       Source of infection: ill person, carrier, ill animals and birds

·       Way of spreading – alimentary or by water; by direct contact, rare air-droplet

·       Susceptible organism: children, especially before 2 years old

Pathogenesis

1.     Massive entering of bacteria to the alimentary canal.

2.     Destruction of salmonella in the upper departments of alimentary canal.

3.     Toxemia → vomit (as a protective factor).

4.     Entering of other bacteria into thin intestinum, colon, colonization of epitheliocytes.

5.     Local inflammatory process, dysperistalsis, digestion and suction imparement, biologically active substance accumulation, which impare absorption of water, electrolytes (diarrhea, dehydration).

6.     Damage of the intestinal, lymphatic barriers (septic form of salmonellosis).

7.     Bacteriemia.

8.     Forming of septic focuses.

Classification

1.     Local form

•         Gastrointestinal form

•          Bacterium carrying

2.     General form

•         Typhoid fever - like

•         Sepsis

3.     Asymptomatic form

    II.            Severity (mild, moderate and severe)

III.            Duration

•         Acute (up to 1.5 mo)

•         Subacute (up to 3 mo)

•         Chronic (more than 3 mo)

IV.            Course

•        Smooth

•         Uneven (with complication)

V. Bacterium carrier

Clinical diagnostic criterions

Of local gastro-intestinal forms:

·        period of incubation: hours (for gastritis) – several days (in case of spreading by direct contact)

·        acute beginning from: intoxication (nausea, vomiting, high body temperature, headache);

·       abdominal pain;

·       diarrhea, usually appears secondary, stools are “muddy” (photo), may be with blood and mucus, abdomen is tender; dehydration is moderate.

 

 

 “Muddy” stools, hemocolitis

Typhoid form

·       acute beginning from high temperature (39-40˚ C) lasting for 1-2 weeks,

·       vomiting, hallucinations;

·       “Typhoid” tongue;

·       hepato-, splenomegaly from the 5-6 day of disease;

·       skin rash (roseols) on the trunk;

·       diarrhea;

·       tenderness in the right inguinal part of abdomen.

 

Septic form

·        Incubation period is long (5-10 days).

·       Usually occurs in newborns, infants with predisposal factors (hypotrophy, rickets so on).

·       Acute beginning from fever that becomes hectic.

·       Septic focus: meningitis, pneumonia, osteomyelitis, pyelonephritis, enterocolitis);

·       hepatosplenomegaly;

·       hemorrhagic syndrome;

·       development of toxic-dystrophic syndrome;

·       relapses,

·       longitude duration, formation of carrying;

·       high mortality;

·       antibiotic resistance, nosocomeal strains of Salmonella;

·       contact way of spreading.

 

Salmonellosis Features in the newborns

·        Generalized form, high lethality.

·        The mechanism of transmission is contact-domestic (through nursery facilities).

·        Sources are mothers, hospital personnel.

·        Agent - hospital strains of Salmonella.

·        High resistance to antibiotics

·        Prolonged latent period (5-10 days).

·        Gradual beginning with growth of clinical symptoms.

·        Severe and prolonged intoxication.

·        Protracted motion, transmitter, relapses.

·        Toxic-dystrophic syndrome development.

 Laboratory tests

·       Complete blood count with differential

•         Cultures: Isolation of Salmonella from cultures of stool, blood, urine, or bone marrow is diagnostic. Specimens should be plated lightly onto Endo-Lewin, Ploskirev, McConkey, xylose-lysine-deoxycholate, or eosin-methylene blue agars.

·       Stool examination: Stool may be hemoccult positive and may be stool positive for fecal polymorphonuclear cells.

·       Chemistry: Electrolyte tests may reveal metabolic acidosis or other abnormalities consistent with dehydration.

·       Serologic tests: (AR, PHAR in dynamics with fourfold title increasing in 10-14 days) in children elder than 1 year if fecal culture is negative.

 

Diagnosis example:

·       Salmonellosis (S. enteritidis), typical local gastrointestinal form (enterocolitis), moderate degree, acute duration. Complication: isotonic dehydration, 1st degree.

·       Salmonellosis (S. typhimurium), typical generalized septic form (enterocolitis, meningitis, bilateral pneumonia, left humeral bone osteomyelitis), severe degree, subacute duration. Complication: malnutrition, 2^nd degree.

 

Differential diagnosis should be performed with: functional diarrhea, shigellosis, escherichiosis, klebsiellosis, typhoid fever, and sepsis of different etiology.

 

Treatment: see treatment of Ecsherichiosis below

Prophylaxis:

 - Epidemiological control.

 - Isolation and sanation of ill person and carriers.

 - Reconvalescent may be discharged from hospital after one negative feces culture (taken 2 days after stop of antibiotic therapy).

 - Dispensarization of reconvalescents for 3 months.

 - Feces culture in contacts, carriers.

 - Looking after contacts for 7 days without quarantine.

 - Disinfection in epidemic focus.

References:

Main:      

1.      Ambulatory pediatric care/ edited by Robert A. Derchewitz; - 2^nd ed. – Lippincot – Raven, 1992. – p. 404-411, P.425-429.

2.      Current therapy in pediatric infections disease – 2/ edited by John D. Nelson, M.D. – B.C. Decker Inc. Toronto, Philadelphia, 1988. – p.74-77, 80-81.

3.      Principles and Practice of Pediatric Infectious Diseases. / Edited by Saran S. Long, Larry K. Pickering, Charles G. Prober, Philadelphia, Pa: Churchill Livingstone; 1997. – 1921 p.

Additional:

1.                         Cleary TG: Yersinia. In: Behrman RE, Kliegman RM, Jenson HB, eds. Nelson Textbook of Pediatrics. 16th ed. Philadelphia: WB Saunders; 2000: 857-859.

2.                         Pickering L, ed: Yersinia enterocolitica and Yersinia pseudotuberculosis infections. In: Red Book: Report of the Committee on Infectious Diseases. 25th ed. Elk Grove Village, Ill: American Academy of Pediatrics; 2000: 642-643.

3.                         Textbook of Pediatric Nursing.  Dorothy R. Marlow; R. N., Ed. D. –London, 1989.-661p.

4.                         Pediatrics ( 2^nd edition, editor – Paul H.Dworkin, M.D.) – 1992. – 550 pp.

5.                         Behrman R.E., Kliegman R.M., Jenson H.B. Nelson nextbook of Pediatrics. - Saunders. - 2004. - 2618 p.

6.                         Castaneda C. Effects of Saccharomyces boulardii in children with Chronic Diarrhoea, Especially Due to Giardiasis // Revista Mexicana de Puericultura y Pediatria. - 1995. - V. 12. - P. 1462-1464.

7.                         Guidelines for control of shigellosis, icluding epidemics due to Shigella type 1/-World Health Organisation, 2005.

8.                         Implementing the New Recommendation on the Clinical Management of Diarrhoea. - World Health Organisation, 2006.

9.                         Klein J.D., Zaoutis T.E. Pediatric Infectious Disease Secrets. - Philedelphia: Hanley & Belfus Inc, 2003. - P. 142.