Primary Tubercular Complex-Plain CXR

A young child with cough and fever

Chest Xray shows subsgemetnal atelectasis with transverse fissure thickening with hilar lymphadenopathy and mottled infrahilar reticulation possibly lymphangitis – together called primary complex disease(Ranke’s complex)

Teaching points by Dr MGK Murthy

-       Tubercle bacilli as little as 1-3 can reach the respiratory tree  of the child invariably from cavitating adult contact usually at home or school/daycare environment as the bacilli are  really killed by ultraviolet light outside

·       The bacilli can be expelled by the cilia to be swallowed and destroyed by the stomach acid or can reach alveoli to be inhibited/killed by the macrophages.

·       If they are virulent , multiply and burst macropahges to spread forming tubercle (aggregation of macrophages, epitheloid cells and lymphocytes)

·       Immune response at this stage(3-8 wks) is delayed hypersensitivity and tuberculin test is positive

·       Bacilli escape from edge, multiply and reach lymphnodes .

·       All the 3 components alveolar site (ghon’s focus), lymphangitis and infected mediastinal lymphnode form Primary complex mediated by cell mediated immunity (Ranke’scomplex)

·       Chest Xray/CT is + by 4-8 wks after the exposure

·       Can involve any part  of the lung but middle lobe is least involved

·       95%do not suffer from disease and X ray  shows only fibrosis, calcification or completely normal

·       Radiological hallmark is lymphadenopathy

·       Because of peculiarity of lymphatics, left parenchymal lesion produces bilateral and right parenchymal shows only right hilar  lymphnodes possibly along with transverse fissure fluid

·       When the lesion erodes the lymphnode and spreads along the bronchus it will become progressive primary TB

·       If TB infection occurs 1 year or later after the original infection, referred to as post primary from usually because of reactivation

·        Post primary prefers colonization in upper lobes specially apical and posterior segments

·       Child to child transmission is rare because of lack of tussive outburst

·       Miliary and Meningeal forms develop in 1st 3months after primary complex

·       Pleural and peritoneal forms take 3-7 months to manifest

·       One variety called congenital TB is extremely rare possibly because  of hypoxic intrauterine environment does not promote TB bacilli growth.

·       But when occurs ,usually via transplacental spread-----primary complex is in liver –periportal LNs –other organs and lungs can remain latent for 2-4 wks after birth and when Xray is +, it shows miliary form

·       Even more rarely can occur by foetus swallowing bacilli in genital TB

Miliary tuberculosis-CT

Miliary tuberculosis (also known as "disseminated tuberculosis" is a form of tuberculosis that is characterized by a wide dissemination into the human body and by the tiny size of the lesions (1–5 mm). Its name comes from a distinctive pattern seen on a chest X-ray of many tiny spots distributed throughout the lung fields with the appearance similar to millet seeds—thus the term "miliary" tuberculosis.

Tree-In-Bud Appearance-CT Sign

The tree-in-bud sign is a finding seen on thin-section computed tomographic  images of the lung . Peripheral, small, centrilobular, and well-defined nodules of soft-tissue attenuation are connected to linear, branching opacities that have more than one contiguous branching site, thus resembling a tree in bud. The tree-in-bud sign has primarily been used as a descriptive term for abnormalities found on CT scans of the lung in patients with endobronchial spread of Mycobacterium tuberculosis.

Sternoclavicular Joint Tuberculosis-MRI

The occurrence of tuberculosis in the flat bones of chest and skull is very rare. With the resurgence of tuberculosis all over the world, there have been reports of unusual sites being affected by the disease. However, cases of clavicular or sternoclavicular tuberculosis are few. The rarity of occurrence of tubercular arthritis of the sternoclavicular joint can be attributed to the peculiar blood supply of this joint. The common conditions, which have to be differentiated from sternoclavicular tuberculosis are low grade pyogenic infections, rheumatoid disease, myeloma or secondary deposits. This is confirmed case of tuberculosis in a 46year old Indian male.

Hepatic Tuberculomas-CT

TB is a growing problem worldwide; consequently, it is vital to recognize the more unusual presentations of this disease. Intra-abdominal TB has a high mortality, but it is a difficult diagnosis to make, often requiring laparotomy. Liver tuberculoma is, in particular, rare, with fewer than 100 cases reported in the literature, most of which are secondary and associated with miliary TB. This is a case of 32 year old female with caviating right upper lobe lesion with miliary mottling and hepatic tuberculomas. Mediastinal lymphnodes are also seen.

Reported by- Teleradiology Providers

Isolated posterior element Potts spine -MRI

Spinal tuberculosis is more common in the eastern countries than in the western world. Recently, there has been a renewed interest in tuberculosis in the west because of its re-emergence, especially in immunocompromised patients (e.g., HIV). The classic radiologic picture of "two vertebral disease with the destruction of the intervertebral disc" is easily recognized and readily treated, but its atypical forms are often misdiagnosed and mistreated. In tuberculosis of the posterior element of the spine, MRI is extremely useful in evaluating the extent of involvement and response to therapy of isolated tuberculosis of posterior elements. Involvement of posterior elements due to tuberculosis is not so uncommon.

Further reading--Isolated tuberculosis of posterior elements of spine: magnetic resonance imaging findings in 33 patients. Spine (Phila Pa 1976). 2002 Feb 1;27(3):275-81

Craniovertebral Tuberculosis-CT

Some CT images showing destruction of the left lateral mass and odontoid tip. Patient is k/c/o of tuberculosis.

Dr.Sumer K Sethi, MD

Sr Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Editor-in-chief, The Internet Journal of Radiology

Director, DAMS (Delhi Academy of Medical Sciences)

Tuberculosis of Ankle-MRI

These are coronal and sagittal Fat suppressed MR images of a patient with tuberculosis involving the Calcaneum, talus, navicular, cuboid and cueniforms. Other diffeential that was considered was madura foot as it is very common in India.

Dr.Sumer K Sethi, MD

Sr Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Editor-in-chief, The Internet Journal of Radiology

Director, DAMS (Delhi Academy of Medical Sciences)

Tubercular Meningitis with Trapped Ventricle-MRI

This is a case of tubercular meningitis with choroid plexitis and trapped temporal horn of lateral ventricle seen on MRI. Note the abnormal enhancment of choroid plexus.
Dr.Sumer K Sethi, MD

Sr Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Editor-in-chief, The Internet Journal of Radiology

Director, DAMS (Delhi Academy of Medical Sciences)

Tuberculosis-The Mimic

This is 31 yr old female who presented acute complaints, inhomogenously enhancing pathology was seen in the cerebllar vermis and a MRI diagnosis of neoplastic etiology was made. Patient underwent surgery and histopathologically turned out to be tubercular infection. Yet another reminder to the fact that TB can mimic any pathology, should be included in differential in endemic areas.

Dr.Sumer K Sethi, MD
Sr Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers
Editor-in-chief, The Internet Journal of Radiology
Director, DAMS (Delhi Academy of Medical Sciences)

Tuberculosis- A Pictorial Radiological Review

Here is a Pictorial Review of Tuberculosis of various organ systems, including classical appearances showing Putty Kidney, Tubercular endometritis, miliary kochs, mediastinal and hilar lymphnodes (classical of primary infection) and ileocaecal kochs. Cases have been compiled by- Dr Sumer Sethi, CEO & Consultant Teleradiology Providers, pioneering Indian Online Radiology Consult.

Tuberculosis of Shoulder-MRI

Here is case of Tubercular involvement of Shoulder by Teleradiology Providers

Interesting Case-Tubercular involvement of Spine with Cord Involvement

Here is a case of tubercular involvement of spine submitted by Dr (Col) MGK Murthy, Senior Consultant Teleradiology Providers with osseous & cord involvement.