Amoebic dysentery vs. Bacillary dysentery
Amoebic dysentery vs. Bacillary dysentery
Acute diarrhea is categorized as noninflammatory (watery, non-bloody) or inflammatory (bloody). The term dysentery refers to bloody diarrhea.
Bloody diarrhea caused by Shigella is often called bacillary dysentery. Other bacterial causes of dysentery are, Vibrio parahaemolyticus, Enteroinvasive E.coli (EIEC), Enterohemorrhagic E.coli (EHEC), Campylobacter sps, and Salmonella sps. Bloody mucous containing diarrhea caused by bacterial pathogens is often accompanied by inflammatory cells (neutrophils). Other symptoms include fever, abdominal cramping, tenesmus, and pain in defecation.
Amoebic dysentery (also known as amoebiasis) is caused by an invasive protozoan parasite, Entamoeba histolytica.
Difference Between Amoebic Dysentery and Bacillary Dysentery
Character | Amoebic dysentery | Bacillary dysentery |
Macroscopic | ||
Number | 6-8 motions a day | Over 10 motions a day |
Amount (Volume) | Relatively copious | Small amount |
Appearance and Amount | Blood mucus, semi formed | Blood mucus, mainly watery |
Odour | Offensive (fishy odour) | Odourless |
Colour | Dark red (altered blood) | Bright red (fresh blood) |
Reaction | Acidic | Alkaline |
Consistency | Not adherent to the container | Adherent to the container |
Microscopic | ||
RBCs | In clumps | Discrete, sometimes in clumps due to rouleaux formation |
Pus Cells | Few | Numerous |
Macrophages | Few | Numerous, many of them contain RBCs hence may be mistaken for E. histolytica |
Eosinophils | Present | Scarce |
Charcot-Leyden (C-L) crystals* | Present | Absent |
Pyknotic bodies** | Present | Absent |
Ghost Cells*** | Absent | Present |
Parasites Seen | Trophozoites of E. histolytica | Absent |
Bacteria Seen | Many motile bacteria | Scanty, nonmotile (Shigella is nonmotile bacteria) |
Culture | ||
Growth on MacConkey Agar | Various intestinal flora may grow | Pure growth of Shigella spp. may be seen |
Further notes:
Figure: Charcot Leyden Crystals
- Charcot-Leyden crystals are hexagonal bipyramidal structures, formed from the breakdown of eosinophils and may be seen in the stool or sputum of patients withparasitic diseases*.
- **Pyknotic bodies are the nuclear remains of tissue cells and leukocytes, they may present in the stools of persons suffering from amoebiasis.
- ***Ghost cell is a swollen/enlarged epithelial cell with only cytoplasmic outline but without a nucleus.
References
- Manson-Bahr, P. E., & Ormerod, W. E. (1971). Amoebic and bacillary dysentery and the enteric fevers. The Practitioner, 207(238), 154–163.
- Cook G. C. (1977). Dysentery-bacillary and amoebic. Nursing mirror and midwives journal, 144(12), 54–57.
- Dans, L. F., & Martínez, E. G. (2007). Amoebic dysentery. BMJ clinical evidence, 2007, 0918.
Tankeshwar Acharya, MSc (Medical Microbiology)
Tankeshwar Acharya is an Assistant Professor in the Department of Microbiology at Patan Academy of Health Sciences (PAHS), Nepal, where he has been teaching and practicing clinical microbiology for over 14 years. He is the founder of Microbe Online, one of the leading free microbiology education resources on the web, covering bacteriology, mycology, parasitology, immunology, and clinical laboratory diagnostics written from direct experience in both the classroom and the diagnostic laboratory.