MICROBIOLOGY TESTS
The purpose of performing Microbiology tests is to detect the germs that cause infectious diseases.
Infectious diseases are diseases caused by Germs (Microorganisms) or their products such as toxins. Infectious diseases are the number one cause of the disease burden in Africa, and are responsible for most of the illness and death on the continent. Infectious diseases may be caused by bacteria, viruses, parasites or fungi. In table 1, examples of infectious diseases and the germs/ organisms causing them are shown.
Infectious diseases diagnostics thus involve the detection of the disease-causing germs/microorganisms in patient samples and/or testing of these germs / organisms to a profile of antibiotics to determine the exact antibiotics that kill the germ/organism before the doctor prescribes for you the correct antibiotic that will work. When the germs are grown in the laboratory and tested against the antibiotics to tell which ones kill them, this process is known as Culture and Sensitivity Testing.
Table 1. Examples of infectious diseases and their causative organisms
| Organism group | Infectious Disease | Example of causative Germs/organisms |
| Bacteria | Pneumonia |
Streptococcus pneumonia |
| Urinary tract infections (UTI) | Escherichia coli, klebsiella pneumonae | |
| Skin ulcers in children | Streptococcus pyogenes | |
| Otitis media | Staphylococcus aureus, haemophillus influenzae | |
| Tuberculosis (TB) | Mycobacterium tuberculosis | |
| Typhoid | Salmonella Typhi or Paratyphi | |
| Syphilis | Treponema pallidum | |
| Brucellosis | Brucella mellintensis or B. Abortus | |
| Dysentery (bloody diarrhoea) | Shigella dysenterae | |
| Bacterial Meningitis | Streptococcus pneumoniae, Nesseria meningitidis | |
| Peptic ulcers | Helicobacter pyroli | |
| Pyomyositis | Staphylococcus aureus | |
| Osteomyelitis | Staphylococcus aureus | |
| Gonorrhea | Nesseria gonorrhae | |
| Blood stream infection | Staphylococcus aureus, salmonella spp | |
| Viruses | Naso-pharyngitis (Sore throat/flu) and pneumonia | SARS-CoV-2 Virus (COVID-19), Influenza, Measles, etc |
| AIDS | HIV | |
| Painful ulcers in genital parts | Herpes simplex virus (HSV) Type 2 | |
| Genital warts | Molluscum contagiosum | |
| Viral Meningitis | Herpes simplex virus (HSV) type 1 | |
| Blood stream viral infections | Cytomegalovirus (CMV) | |
| Skin infections | Molluscum contagiosum | |
| Fungi | Nails/Hair/Skin fungal infections in children/adults | Many species of fungi cause these |
| Vaginal candidiasis | Candida albicans | |
| Blood stream fungal infections | Candida albicans – in patients with blood/bone marrow cancer | |
| Fungal Meningitis | Cryptococcus neorfomans | |
| Disseminated organ fungal infections | Several Dimorphic fungi | |
| Parasites | Malaria | Plasmodium falciparum or other species |
| Intestinal hookworm disease | Hook worms | |
| Intestinal tape worm disease | Taenia saginata, or T solium | |
| Trypanosomiasis | Trypanosoma gambience | |
| Filariasis (River blindness or Elephantiasis) | Oncocerca volvulus | |
| Schistosomiasis | Schistosoma haematobium, S. Mansoni | |
| Persistent Diarrhoea | Cryptosprodium parvunm or other species |
Due to the worldwide growing problem of drug resistance, it is very critical that the patient caring doctor gets to know exactly the organism in the patient sample, and its drug susceptibility profile thru culture and sensitivity testing.
MBN Clinical Laboratories offers, seamlessly and professionally, culture and sensitivity testing services, and also performs molecular/DNA-based tests to help determine the causative germs and their susceptibility to antibiotics.
I am text block. Click edit button to change this text. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.
SAMPLE & MICROBIOLOGY TESTS
Ascites/Pleural/Joint/Pericardial/Hydrocele Fluids (10-20 mls in sterile tube)
Cell counts, Gram, ZN, Protein, Sugar, LDH
Culture & Sensitivity
Biopsy tissue
Gram and ZN stain
KOH + Calcoflour (fungal hyphae)
Culture & Sensitivity (Sample collected in plain sterile container with 1-2 mls sterile N.saline)
Histopathology test, collect sample in 10% Formalin
Pap Smear to screen for cancer of the Cervix
Blood
B/S Malaria/Trypanosoma/Filaria/Leishman)
Malaria antigen test (P. falc & P. ovale )
Blood culture & Sensitivity – Manual monitoring
Blood culture & Sensitivity – Automated monitoring
Bone marrow (1-2ml in sterile tube)
Bone marrow Smear/film
Culture & Sensitivity (bacteria / fungi)
Breast milk (5-10ml in sterile tube)
Gram, ZN stain, Culture & Sensitivity
BAL/Endotrachael fluid (3-5 mls in sterile tube)
Gram, ZN and Auramine stain
Giemsa stain (Pneumocyctis jirovecii/PCP)
Culture & Sensitivity (bacteria / fungi)
Mycobacterial Culture & Sensitivity
Catheter Tip (2-3cm tip, cut into 1ml sterile N/S)
Culture & Sensitivity (bacteria / fungi)
CSF (1-3ml in sterile tube, 1ml in Fluoride bottle for Sugar)
Cell counts – T & D, India ink, Gram & ZN stain, Sugar, Protein
Culture & Sensitivity (bacteria / Yeasts e.g. Cryptococcus)
RPR/ VDRL and TPHA with titers
CRAG (Cryptococcal antigen) test
Corneal Scraping (In Sterile tube/petridish)
Gram, ZN, KOH+Calcoflour white stain
Culture for ameoba
High Vaginal /Cervical Swab
Wet prep for TV, & Gram stain for clue cells
Culture & Sensitivity(Grp B strep or Neisseria)
Gastric Aspirate/biopsy (3-5 mls or g in sterile tube)
ZN for AFBs
Culture for Helicobacter pylori or Mycobacteria
Lymph node Aspirate (3-5 mls in sterile tube)
Gram, ZN and auramine stain
Culture & Sensitivity (bacteria / fungi)
Mycobacterial Culture & Sensitivity
Nasal swab (in amies transport medium)
Culture & Sensitivity to r/o MRSA
Nasopharyngeal/Oropharyngeal swab (in amies transport medium)
Direct Agglutination test (Group A β–haem strept)
Culture & Sensitivity (Group A β-haem strept)
Pus 2-3ml in sterile tube or pus swab in amies transport medium. Body site:__________
Gram & ZN stain, Culture & Sensitivity (bacteria / fungi)
Anaerobic Culture & Sensitivity (only for pus in tube)
Semen
Volume, PH, Spermatozoa motility, Morphology, Count
Culture & Sensitivity
Skin/Hair/ Nail Scrapping (in sterile petri dish)
KOH+ Calcoflour white stain (fungal hyphae/ yeasts)
Culture & Sensitivity for fungal diagnosis
Sputum – Coughed out/Induced (≥3ml, sterile tube)
Gram, ZN and Auramine stain
Giemsa stain (Pneumocyctis jirovecii/PCP)
Culture & Sensitivity (bacteria / fungi)
Mycobacterial Culture & Sensitivity
Stool 3-5g or mls in sterile dry tube; (If for O&P, put in 10ml of 10% Formalin)
Direct wet/iodine mount microscopy
Processed stool then iodine mount microscopy, Trichrome staining for Ova&Parasites and Modified ZN for protozoa such as Cryptosporidium oocysts)
Methylene blue test for PMN Cells
Culture & Sensitivity (Salmonella/Shigella/C.jejuni/Yersinia/Enterohaemorrhagic E. coli/H. pylori/Vibriocholerae)
Reducing sugars in stool
Sudan III test for stool fat
Urethral/Rectal Swab (collect into Modified Thayer-Martin medium or inoculate a chocolate plate immediately).
Gram, ZN stain, Culture & Sensitivity
Urine (5 -10mls in sterile tube)
Microscopy (WBCs, RBCs, epithelial cells, casts, eggs)
Gram & ZN stain on sediment
Culture & Sensitivity