Salmonellosis, symptoms of salmonellosis.

Salmonellosis treatment.

Salmonellosis is a poly-etiological infectious disease, caused by a variety of bacterial serotypes of species Salmonella. The disease is characterized by different clinical manifestations ranging from asymptomatic course to grave septic forms. Most commonly Salmonellosis progresses with lesions of alimentary tract (gastroenteritis, colitis). The causative agent of Salmonellosis is an extensive group of salmonellas (familia Enterobacteriaceae, genus Salmonella), represented at present by over 2200 serotypes.

Primary sources of infection are domestic animals and birds, though human beings also play significant part (sick persons) as infection vectors.

The main invasion way of infection is eating food containing great number of salmonellas. Most commonly this stems from violation of sanitary requirements during cooking or food processing. Salmonellosis treatment.

Symptoms of salmonellosis

The incubation (latent) period during alimentary salmonella infection ranges from 6 hours to 3 days (commonly 12-24 hours). During clinical occurrences when contact infection transmission prevails the latent period may extend to 3-8 days. There may be distinguished the following clinical forms of Salmonellosis:

• The gastrointestinal (localized) one, developing in the gastroenteritis, gastroenterocolitis and enterocolitis variants
• The generalized form progressing as a typhoid-like or septic variant
• Bacteria carrying form: acute, chronic and transitory; subclinical form

The manifested forms of salmonella infection are distinguished by case severity.

The gastrointestinal form (acute gastritis, acute gastroenteritis or gastroenterocolitis) is one of the most common forms of Salmonellosis (96-98% of cases). Acute onset of the disease is manifested by general weakness, headache, chills, nausea, vomiting, pains in the epigastral and navel areas, later aggravated by diarrhea. Sometimes patients complain of fever and the symptoms of general intoxication only while the gastrointestinal disorders develop a while later. The symptoms become most pronounced by the 2-3 day after the onset of the disease. Clarity and duration of the disease manifestations depend on the case severity.

In light salmonellosis cases the temperature is subfebrile, vomiting is singular, stool is watery up to 5 times a day, diarrhea may last 1-3 days, dehydration may not exceed 3% of the body mass. During medium-severity salmonellosis temperature may rise to 38-39° C, fever may last as long as 4 days, repetitive vomiting, stool frequency up to 10 times a day, diarrhea duration is up to 7 days, blood pressure drops may be observed, I-II degree dehydration may result in liquid loss amounting to 6% of the total body mass. Severe gastrointestinal Salmonellosis is characterized by high fever (39° C and above) which may last 5 days and longer, by a pronounced intoxication. Vomiting is repetitive, and may persist for several days, stool is frequent (over 10 times a day), profuse, watery and foul-smelling, sometimes with admixture of mucus. Diarrhea may last 7 days and longer. One can observe hepatomegaly and splenomegaly, yellowish coloring of skin and scleras, cyanosis of skin, tachycardia, considerable arterial pressure drop. Kidney disorders may be manifested by oliguria, albuminuria, presence of erythrocytes and casts in urine, urea nitrogen content rise. Acute renal failure may develop. Deterioration of the water-salts metabolism (II-III degree dehydration), which is manifested by skin dryness, cyanosis, aphony, cramps. Loss of liquid may amount to 7-10% of the body mass. Blood hemoglobin and erythrocyte levels rise, a moderate leukocytosis with a characteristic left shift of the leukocyte formula can be observed.

The gastroenteric form is most common clinical form of the gastrointestinal Salmonellosis. Destructive effects in the colon (of catarrho-hemorrhagic nature) are observed in 5-8% of cases only. Gastroenterocolitic and colitic variants of the disease must be diagnosed as such only when the colitis manifestations prevail in the disease clinical characteristics and there is sufficient bacteriological and serological evidence since the progress of these forms of the Salmonellosis is very similar to acute dysentery.

The typhoid-like variant of the generalized salmonellosis. The onset of the disease develops severely. Some patients may have intestinal upset in combination with fever and general intoxication as the first symptoms, but in 1-2 days the intestinal disorders disappear, while the high temperature persists and the general intoxication signs grow. In the majority of cases at the initial stages the course of the disease is similar to abdominal typhoid or paratyphoids A or B. Fever may be either continuous, remittent or come in fits. The patients are retarded and have apathy. The face is pale. In some cases the on the 2-3 day the patients develop herpetic rash and by the 6-7 day roseolus eruption most commonly abdominal. Relative bradycardia, low arterial pressure, and quiet heart murmurs can be observed. Diffuse dry rales can be heard above the lungs. The abdomen is bloated. By the end of the 1^st week hepatomegaly and splenomegaly develop. Fever lasts 1-3 weeks. Recurrence is rare.

Septic Salmonellosis is the most severe variant of the generalized salmonella infection. The onset of the disease is acute and its progress during the first days is similar to typhoid. Later the state of the patients worsen. The temperature becomes erratic with dramatic daily variations, recurrent chills and profuse sweating. The disease progresses gravely and poorly responds to treatment with antibiotics. Secondary septic localities may form in various organs resulting in an extensive variety of manifestations, which make diagnosis of the disease difficult. The developed purulent localities are in the foreground of diagnostics. The purulent processes are often observed in lower extremities: osteomielitis, arthritis. One may develop septic endocarditis, aortitis leading to aortic aneurysm. Relatively frequent are cholecystocholangitis, tonsillitis, purulent lymphadenitis, and meningitis (the latter being more common in children). Other purulent localities are less common, for example liver abscess, infection of ovarian cyst, salmonella-caused strumitis, mastoiditis, abscess of buttocks.

The septic Salmonellosis is characterized by a lengthy course with possible lethal outcome especially when complicated by HIV infection. The disease is usually diagnosed when salmonellas are found in the pus from the secondary purulent locality or in blood sample during the first days of the disease.

In babies before 1 year old and in patients over 60 the disease progresses with greater severity with more frequent incidence of the colon pathologies, slower stool normalization and more frequent development of the generalized forms of the ailment.

Bacteriohosting. This form of the disease lacks clinical symptoms and is determined only by bacteriological and serological tests. Salmonella hosting is divided into the following three categories: 1) acute hosting; 2) chronic hosting and 3) transitory hosting.

Acute hosting is observed in convalescents after manifested forms of Salmonellosis and is characterized by release of salmonellas lasting 15 – 90 days.

Chronic hosting occurs if the salmonella release period lasts over 3 months. To confirm the salmonella chronic hosting diagnosis the patient is to be observed for 6 months at least with periodic blood, urine, feces and duodenal content examinations. The serological test used for the diagnostic purposes is the indirect hemagglutination (IHA) reaction.

Transitory salmonella hosting may be diagnosed when clinical manifestations lack on the date of examination and were not observed for 3 months before and at the same time the bacteriological tests yielded positive results once or twice with one day interval with subsequent negative testing. Besides repetitive serological tests (IHAR) with a Salmonellosis diagnosticum must be negative.

Subclinical form of Salmonellosis is diagnosed when salmonellas are found in feces and contra-salmonellas antibodies are revealed in diagnostic titres of serological reactions. There are no clinical manifestations of the disease in such cases.

Salmonellosis treatment.