Sonography In Hiv

SONOGRAPHY IN HIV/TB

Sonography In Hiv

The Focused Assessment with Sonography for HIV/TB (FASH) protocol, has been developed to help diagnose the extrapulmonary and disseminated forms of tuberculosis (TB) that are frequently seen in patients who have the human immunodeficiency virus (HIV) The main objectives of the FASH ultrasound exam are to detect effusions that may suggest pleural, pericardial, or abdominal TB; enlarged abdominal lymph nodes; and focal lesions in the spleen, which may suggest miliary or disseminated TB encountered in severely immunocompromised patients.

Sonography of Abdominal Lymph Nodes and

Spleen: The FASH Protocol

In recent years, ultrasound has proved to be a useful tool in evaluating HIV patients suspected of co-infection with EPTB.

Detection of abdominal lymphadenopathy and splenic microabscesses are typical findings suggestive of abdominal TB.

SONOGRAPHIC FINDINGS

Normal lymph nodes are small round or oval structures whose size ranges from a few millimetres up to 1 cm; they are usually not visible in the abdomen unless they are enlarged.

The parietal nodes are located in the retroperitoneum, close to the large vessels .

These nodes are a continuation of the lymphatics, which drain from the lower half of the body.

The visceral lymph nodes are located at the root of the mesentery as well as in the portal area. They drain lymphatics from the bowels, pancreas, and hepatobiliary system.

Sonography In Hiv

Although normal-sized abdominal lymph nodes cannot be detected through ultrasound, superficial lymph nodes (such as those in the axilla or the inguinal region) may be visible, especially when using high-frequency linear transducers.

When visible, they appear as round, hypoechoic structures surrounded by a connective tissue capsule, and often show an echogenic center (hilus fat sign) due to central fat and connective tissue

The parenchyma of the spleen is homogenous, with a fine, velvet-like echo pattern.

• It resembles the liver, but is often slightly less echogenic.

Lobulation with a variable outer contour of the spleen can be seen as a normal variant.

Accessory spleens are often located in the hilar region of the spleen, along the gastrosplenic ligament, or at the caudal pole of the organ.

They have the same echo pattern as the spleen itself, are often round, and are usually small (< 2.5 cm).

Lymph nodes larger than 1.5 to 2 cm are considered pathological in an adult with HIV.

Pathological enlarged nodes in TB are often hypoechoic and rounded. The markedly low echogenicity is due to loss of internal structures caused by caseous necrosis.

The lymphadenopathy may be discrete, or nodes might be conglomerated into a larger mass.

On rare occasions, tuberculous lymph nodes may appear hyperechoic. Lymph node masses may cause obstruction of ureters, the pancreas, and biliary tract, or (less often) the digestive system.

Splenic lesions

In patients with disseminated TB, splenic microabscesses may appear as multiple small hypoechoic lesions a few millimetres in size.

• These microabscesses are distributed throughout the spleen and represent miliary seeding.

Again, as the transducer fans through the spleen, they will appear to be blinking.

Sonography of the Heart

Ultrasound is an excellent tool for evaluating the aetiology of dyspnoea, peripheral oedema, and the source of cardiomegaly seen on a CXR.

Congestive heart failure (CHF) is probably the most common cause of these symptoms and findings; however, there are also other causes, which are treated differently.

Sonography In Hiv

In an HIV-prevalent tropical setting, common cardiac causes of dyspnoea and oedema are pericardial effusion with tamponade (most often due to TB), dilated cardiomyopathy (for example, peripartum or HIV-cardiomyopathy), post-rheumatic heart disease (causing mitral valve disease in particular), cor pulmonale, and hypertensive heart disease.

Sonography of the Renal

Renal and urinary tract disease is common in adults and children throughout all continents.

Numerous protocols for point-of-care renal and bladder ultrasound examination have been developed, especially for patients with flank pain or abdominal pain and urinary symptoms.

These protocols focus on identifying hydronephrosis, bladder distension, and stone disease.

Sonography In Hiv

The aetiologic spectrum leading to urinary tract obstruction is broad: common causes of urinary tract obstruction in resource-limited settings include external compression of the ureters from lymphadenopathy due to malignancy, TB, or other masses; occlusion of the ureters from stone disease; and chronic infections, such as urinary schistosomiasis.

Sonography In Hiv

Calcification at any level along the urinary tract (including the kidneys) may be a consequence of TB, arising either from concomitant metabolic conditions or from the side effects of drugs, such as the protease inhibitor atazanavir

HIVAN

In ultrasound examinations of patients with HIV, normal-sized kidneys with hyperechoic cortex are often seen.

• The pyramids may seem slightly hypoechoic in comparison.
• These changes may be found even when the results of renal function tests are normal.

Focal segmental glomerulosclerosis is the most frequent underlying pathology of HIVAN.

The morphology is non-specific; it can also be found in other renal diseases, such as diabetic glomerulosclerosis and other forms of chronic glomerulonephritis.

Sonography of the liver

• Involvement of the liver in TB is common (up to 80% in autopsies of PTB).
• On histological analysis, multiple hepatic granulomata are often present.

Clinical manifestations of this involvement are less frequently seen.

Elevations of alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) are the most frequent laboratory findings, though these are non-specific.

Hypo- and hyperglobulinemia are common, although these are more indicative of chronic tuberculous disease than of hepatic synthesis dysfunction.

Sonography In Hiv

Two forms of liver involvement can be sonographically distinguished. In some patients, a diffuse homogenous hepatomegaly is seen, often with a bright echo pattern .

This can be misdiagnosed as fatty infiltration, but when biopsied shows hepatic granulomatous disease. These findings are also described as granulomatous hepatitis, but this is a misnomer—hepatic granulomas generally do not affect liver cells

Sonography In Hiv

Sonographic changes in abdominal and disseminated TB are found in the lymph nodes and spleen. However, there are other findings associated with TB in the abdominal cavity that are more subtle and thus more difficult to recognise.

These findings are discussed here for clinicians who have more ultrasound experience

TB are found in the lymph nodes and spleen .

However, there are other findings associated with TB in the abdominal cavity that are more subtle and thus more difficult to recognise.

Sonography In Hiv

The peritoneum is the most frequent abdominal site of extrapulmonary TB (comprising about half of abdominal cases); overall, the abdomen is third most frequent location of all extrapulmonary TB cases. TB peritonitis It is mainly caused by haematogenous spread and reactivation of long-latent foci or mesenteric lymph nodes, but contiguous spread from the bowel or fallopian tubes is also possible.

The main clinical symptoms of TB peritonitis are ascites and fever. Abdominal pain, reported in about half of TB patients, is most often moderate; rarely does the pain mimic acute peritonitis

Sonography In Hiv

The hallmark ultrasound finding is ascites. Ascites can be clear or complex, with fixed membranes, septa, strands, and floating debris.

Ascites in abdominal TB has characteristics of an exudate (protein content > 2.5 g/dL); often a moderate amount of leukocytes (150–4000) will be found, with a lymphocytic predominance.

Ascites is usually straw-coloured, but in some cases may be blood stained.

TB of the bowel

Although tuberculosis can involve any portion of the gastrointestinal tract, there is a striking predilection for the area of the ileocecal valve, adjacent ileum, and ascending colon.

This may be due to the abundance of lymphoid tissue located within Peyer’s patches in this area.

During the ultrasound exam, concentric, hypoechoic bowel wall thickening resembling other forms of bowel inflammation

TB of the pancreas

Pancreatic involvement in tuberculosis is rare. When it does occur, in addition to the systemic symptoms of tuberculosis, it may present with symptoms of pancreatitis.

Focal tuberculomas can obstruct the pancreatic duct, thereby causing secondary pancreatitis.

Hypoechoic lesions in the pancreas are seen

Diagnostic ultrasound 5th edition by Carol Rumack 2018

ULTRASOUND MANUAL FOR HIV AND TB Tom Helder 2019