Diarrhea: what it is, causes and treatment

What is it

Diarrhea, or dysentery, is a disorder of the intestine that manifests itself with frequent discharges of liquid or semi-liquid stools. It should be considered a symptom and not a disease.

According to its duration, a distinction can be made between:

• acute diarrhea, if it lasts less than 2 weeks;
• chronic diarrhea, if it is present for more than 3-4 weeks.

To speak of real diarrhea, the discharges must be greater than or equal to three per day and the normal consistency of the stool must be altered. In general, it can be said that diarrhea becomes chronic when it persists every day for more than 3-4 weeks.

In addition, it is important to distinguish a condition of real diarrhea from the occurrence of a single discharge of liquid or semi-liquid stools, which can appear suddenly and seemingly without a specific cause. In this regard, let’s see what are the most common causes of diarrhea, how to recognize it correctly and when it is necessary to contact a specialist to carry out an accurate medical examination.

Causes

The appearance of diarrhea may depend on the ingestion of water and food contaminated with viruses, bacteria or parasites. Among the viruses most often implicated in this type of gastrointestinal infection are norovirus and rotavirus, while bacterial forms are often attributable to Campylobacter, Escherichia coli, Salmonella and Shigella. Giardia, a microorganism that lives in water, is mainly responsible for parasitic forms.

Another bacterium linked to diarrhea disorder is Clostridium difficile. Clostridium difficile infection can present with very intense symptoms, including liquid diarrhea, nausea and vomiting, loss of appetite and inflammatory bowel disease, linked to colitis and abdominal pain.

In some cases, viruses can be effectively countered thanks to a special vaccine, which can be administered as early as the first weeks of life. Vaccines help to greatly decrease the risk of severe episodes of diarrhea in children, which can also occur throughout the growth period.

Other types of viruses, on the other hand, can come into contact with the body when you decide to travel to a foreign country; viruses that could cause a particularly strong symptomatology in the most sensitive subjects. For example, acute gastroenteritis also includes traveler’s diarrhea that affects those staying in countries with a hot-humid climate and poor sanitation conditions. The main foods at risk for this type of diarrhea are: shellfish, eggs, raw or undercooked meat, vegetables and fruits washed with contaminated water, unpasteurized dairy products, drinks with ice.

Diarrhoea can also originate from a food intolerance (lactose, gluten), excessive consumption of sweeteners or the use of antibiotics that damage the intestinal bacterial flora.

Lactose intolerance, specifically, is due to the lack or reduced production of lactase, the enzyme responsible for digesting lactose. In those who are intolerant, the consumption of milk and dairy products containing this sugar causes a reaction that manifests itself with more or less intense gastrointestinal disorders. The undigested lactose accumulates, in fact, in the intestine where it draws water and is fermented by the microorganisms of the intestinal bacterial flora, causing diarrhea, flatulence, bloating and abdominal pain.

In the case of celiac disease, caused by a permanent intolerance to gluten, the consumption of foods containing this protein complex (including wheat, spelt, kamut, barley and rye) causes an adverse reaction of the immune system at the level of the small intestine, which is thus damaged, making it more difficult to absorb the different nutrients. In about 25 to 30 percent of cases, celiac disease presents with characteristic symptoms such as diarrhea, weight loss and abdominal pain.

As for sweeteners, among those that, if used in excessive doses, can cause diarrhea and abdominal bloating, we remember for example sorbitol, mannitol and xylitol. These sugars, once reached the last portion of the intestine, generate gas because they undergo fermentation processes by the microorganisms of the intestinal flora.

In general, those who have specific intolerances or are predisposed to suffer from gastrointestinal disorders, should pay more attention to all the elements contained in the foods purchased. Even single traces, as in the case of gluten intolerance, could trigger an inflammatory reaction and, consequently, diarrhea and gas emission (flautulence).

Even a diet too rich in fat (mainly contained in packaged foods), an excessive amount of caffeine or an excessive consumption of fiber, could be contributing causes of a situation of acute or chronic diarrhea.

Diarrhea can also be caused by impaired bowel motility typical of irritable bowel and other chronic inflammatory bowel diseases (Crohn’s disease, ulcerative colitis) or appear as a result of emotionally stressful events.

Those suffering from irritable bowel syndrome present, in particular, an alteration of the motility of the intestine and the sensitivity of the viscera. Typical symptoms are abdominal cramps and alterations in intestinal regularity, with phases of diarrhea or constipation.

Very often, unlike other disorders, irritable bowel syndrome is linked to a situation of anxiety and psychological malaise. The intestine, in fact, is particularly sensitive to mood swings, and represents a very important alarm bell in this sense. However, the food intolerances mentioned above or excessive alcohol consumption can also be the cause of inflammation of the final tract of the intestine.

Crohn’s disease and ulcerative colitis are two inflammatory bowel diseases characterized by a chronic inflammatory process of intestinal tracts. Crohn’s disease can affect the entire digestive system, from the mouth to the anus, but the most common form, which affects about two-thirds of sufferers, is the one that affects the last stretch of the small intestine (the terminal ileum) and generally manifests _{itself with} three symptoms not always present at the same time: chronic diarrhea, weight loss and recurrent stomach pain. Ulcerative colitis, on the other hand, affects only the rectum and / or colon with continuous inflammation that affects the most superficial layers of the intestinal mucosa. The typical symptoms, which occur from the onset of the disease, are abdominal pain and diarrhea mixed with blood.

Sometimes diarrhea is one of the symptoms of diverticulitis, or inflammation of the intestinal diverticula, small extroflexions that form in the wall of the digestive system, almost always at the level of the last portion of the intestine.

Among the most common causes of diarrhea must also be mentioned the side effects of antibiotic therapy: antibiotics could temporarily damage the intestinal bacterial flora, exposing the digestive system to the risk of inflammation. An overdose of laxatives or the use of chemotherapy drugs can also lead to the same consequence.

Finally, episodes of diarrhea are quite common even during pregnancy.

If you want to know what to eat and what to avoid in case of diarrhea read this article.

Sintomi associati comuni

Le scariche di diarrea si associano spesso a dolore addominale, nausea, vomito, debolezza, stanchezza e disidratazione. A volte può comparire anche la febbre. Altri sintomi talvolta associati alla diarrea sono il mal di testa e la perdita di appetito.

Le forme acute sono caratterizzate da numerosi attacchi concentrati in pochi giorni; nelle forme croniche, invece, la diarrea persiste anche per mesi con conseguente malassorbimento degli alimenti.

In quest’ultimo caso, soprattutto se la diarrea non si manifesta con feci totalmente liquide, si tende a sottovalutare il disturbo, limitandosi all’assunzione di probiotici e farmaci antidiarroici. Niente di più sbagliato: quando si verifica una situazione di sintomatologia cronica, è necessario consultare il proprio medico.

Complicazioni

Soprattutto nei bambini piccoli e negli anziani, la principale complicazione della diarrea è l’eccessiva perdita di liquidi e sali minerali con le feci.

I sintomi della disidratazione che ne consegue sono bocca asciutta, vertigini, urine scure e aumento della frequenza cardiaca. Altri segni di disidratazione sono inoltre pelle secca, pallore cutaneo e occhi infossati.

Se sopraggiungono questi sintomi, è importante assumere quanto prima un quantitativo di acqua sufficiente alla reidratazione dell’organismo per farlo tornare alla sua piena funzionalità. In alcuni casi, sarà necessario utilizzare integratori di elettroliti, come magnesio e potassio, per reinserire il quantitativo perso durante la disidratazione. Anche il consumo di frutta ricca di potassio come le banane può aiutare allo scopo.

In altri casi, è possibile rilevare la presenza di sangue nelle feci. In questo caso, è necessario rivolgersi appena possibile al proprio medico di fiducia, perché la diarrea potrebbe essere il sintomo di una patologia più grave.

Diagnosi

Può capitare a chiunque di soffrire di episodi di diarrea. Nella maggior parte dei casi il sintomo si risolve in pochi giorni, ma se ciò non accade bisogna rivolgersi al medico di famiglia che, per identificarne le cause, potrebbe prescrivere alcuni esami del sangue e strumentali.

Se si sospetta una gastroenterite in genere non servono esami per confermare la diagnosi, fatto salvo alcune situazioni più delicate, per esempio qualora si abbia a che fare con bimbi affetti da patologie croniche o con sintomi severi e duraturi, tali da richiedere il ricovero in ospedale. In questi casi, attraverso gli esami microbiologici, si può individuare il germe responsabile e instaurare un trattamento mirato.

Se si sospetta che i disturbi della defecazione siano conseguenza di un’intolleranza al lattosio si può ricorrere al breath test o test del respiro (che consiste nel far soffiare il paziente dentro uno speciale palloncino, prima e dopo avergli somministrato lattosio), mentre se si ipotizza un’intolleranza al glutine vanno dosati gli anticorpi anti-transglutaminasi e anti-endomisio.

To diagnose Crohn’s disease, an endoscopic examination of the affected intestinal tract with histological examination is first required. In general, other tests must be performed later, such as, for example, ultrasound of the intestinal loops, enema of the small intestine, CT scan or magnetic resonance imaging depending on the specific case. In the case of ulcerative colitis, the symptoms are already very clear and to have a confirmation it is usually sufficient colonoscopy with histological examination.

To trace the cause of diarrhea, in specific cases it may also be useful to perform digital rectal examination.

When to consult your doctor

If along with diarrhea appears blood in the stool or high fever you should seek medical attention.

The doctor should also be consulted when, regardless of diet and treatment, diarrhea does not resolve or is recurrent. Underestimating the symptom without resorting to a specialist consultation could lead the disease to worsen, compromising the correct intestinal transit and making the disorder debilitating for the patient.

In some cases, the prolonged inflammatory state concomitant with the weakening of the intestinal membrane could extend to the urinary tract, causing urination problems.

Prevention

Since one of the most common causes of diarrhea is represented by viral and bacterial infections, it is possible to implement some preventive measures, first of all respecting high standards of hygiene. For this reason it is advisable to wash your hands thoroughly and often with warm water and soap, especially after going to the bathroom and before eating or preparing food, and to avoid sharing towels, napkins, cutlery, glasses or utensils with others. To prevent food poisoning it is also useful not to store raw and cooked food together and always cook food accurately.

To keep away the traveler’s diarrhea when traveling to countries at risk, avoid drinking tap water and do not add ice to drinks, do not eat raw or undercooked seafood, meat and chicken not cooked thoroughly, avoid unpasteurized milk and dairy products and give up salads and raw vegetables. In this way it is possible to minimize the risk of taking pathogens and toxins.

To prevent viral infection with Rotavirus, the most common cause of gastroenteritis in children under 5 years, there are also vaccines that can be administered by mouth in the first months of life, very valid to reduce episodes and especially their severity.

Finally, a balanced and controlled diet can be useful to limit the risks of diarrhea, especially when suffering from irritable bowel syndrome.