Mycobacterium haemophilum
Encyclopedia
Mycobacterium haemophilum
, nonmotile and strongly acid-fast
rods.
Colony characteristics
Physiology
Differential characteristics
Distribution.
from a patient with Hodgkin's disease. An environmental reservoir is presumed.
Strain ATCC 29548 = CCUG 47452 = CIP 105049 = DSM 44634 = NCTC 11185.
Description
Short, occasionally curved, gram-positiveGram-positive
Gram-positive bacteria are those that are stained dark blue or violet by Gram staining. This is in contrast to Gram-negative bacteria, which cannot retain the crystal violet stain, instead taking up the counterstain and appearing red or pink...
, nonmotile and strongly acid-fast
Acid-fast
Acid-fastness is a physical property of certain bacteria, specifically their resistance to decolorization by acids during staining procedures.Acid-fast organisms are difficult to characterize using standard microbiological techniques Acid-fastness is a physical property of certain bacteria,...
rods.
Colony characteristics
- Nonpigmented and rough to smooth colonies.
Physiology
- Media have to be supplemented with 0.4% haemoglobin or 60µM heminHeminHemin is an iron-containing porphyrin. More specifically, it is Protoporphyrin IX containing a ferric iron ion with a chloride ligand....
(factor XFactor XFactor X, also known by the eponym Stuart-Prower factor or as prothrombinase, is an enzyme of the coagulation cascade. It is a serine endopeptidase .-Physiology:...
) or 15 mg/ml ferric ammonium citrate respectively, but not with FeCl3 or catalaseCatalaseCatalase is a common enzyme found in nearly all living organisms that are exposed to oxygen, where it catalyzes the decomposition of hydrogen peroxide to water and oxygen...
. - Slow growth on Löwenstein-Jensen media or Middlebrook 7H10 agar at 32°C within 2–4 weeks.
- Growth slower at 25°C and 35°C and absent at 37°C.
- Strictly intracellular growth in tissue cultures of fibroblasts.
Differential characteristics
- Unique among mycobacteria in its requirement for heminHeminHemin is an iron-containing porphyrin. More specifically, it is Protoporphyrin IX containing a ferric iron ion with a chloride ligand....
or ferric ammonium citrate for growth.
Distribution.
Pathogenesis
- Infects patients with suppressed immune systems.
- Clinical presentation: multiple skin nodulesNodule (medicine)For use of the term nodule in dermatology, see Nodule In medicine, a nodule refers to a relatively hard, roughly spherical abnormal structure....
occurring in clusters or without definitive pattern, commonly involving the extremities. Abscesses, draining fistulaFistulaIn medicine, a fistula is an abnormal connection or passageway between two epithelium-lined organs or vessels that normally do not connect. It is generally a disease condition, but a fistula may be surgically created for therapeutic reasons.-Locations:Fistulas can develop in various parts of the...
s and osteomyelitisOsteomyelitisOsteomyelitis simply means an infection of the bone or bone marrow...
may be associated with the nodules. Paediatric patients with localised cervicalCervical lymph nodesCervical lymph nodes are lymph nodes found in the neck.-Classification:There are approximately 300 lymph nodes in the neck, and they can be classified in many different ways.Henri Rouvière produced an influential classification in 1938...
lymphadenopathyLymphadenopathyLymphadenopathy is a term meaning "disease of the lymph nodes." It is, however, almost synonymously used with "swollen/enlarged lymph nodes". It could be due to infection, auto-immune disease, or malignancy....
. - Biosafety levelBiosafety levelA biosafety level is the level of the biocontainment precautions required to isolate dangerous biological agents in an enclosed facility. The levels of containment range from the lowest biosafety level 1 to the highest at level 4 . In the United States, the Centers for Disease Control and...
2
Type strain
First isolated in Israel from a subcutaneous granulomaGranuloma
Granuloma is a medical term for a tiny collection of immune cells known as macrophages. Granulomas form when the immune system attempts to wall off substances that it perceives as foreign but is unable to eliminate. Such substances include infectious organisms such as bacteria and fungi as well as...
from a patient with Hodgkin's disease. An environmental reservoir is presumed.
Strain ATCC 29548 = CCUG 47452 = CIP 105049 = DSM 44634 = NCTC 11185.