Anindita Sinha

Congenital Extrahepatic Portosystemic Shunts: Spectrum of Findings on Ultrasound, Computed Tomography, and Magnetic Resonance Imaging.

Congenital extrahepatic portosystemic shunt (CEPS) is a rare disorder characterised by partial or complete diversion of portomesenteric blood into systemic veins via congenital shunts. Type I is characterised by complete lack of intrahepatic portal venous blood flow due to an end to side fistula between main portal vein and the inferior vena cava. Type II on the other hand is characterised by partial preservation of portal blood supply to liver and side to side fistula between main portal vein or its branches and mesenteric, splenic, gastric, and systemic veins. The presentation of these patients is variable. Focal liver lesions, most commonly nodular regenerative hyperplasia, are an important clue to the underlying condition. This pictorial essay covers imaging characteristics in abdominopelvic region.

Multidetector Computed Tomography and MR Imaging Findings in Mycotic Infections

Fungal infections constitute a diverse spectrum of infections with variable clinical and imaging features. They are commonly opportunistic infections that affect immunocompromised individuals secondary to inherited or acquired disorders. Fungal infections may affect multiple organ systems and contribute to significant morbidity and mortality. Although the imaging features of some fungal infections are characteristic and permit their diagnosis, many mycotic infections manifest nonspecific findings. Definitive diagnosis often depends on histopathological analysis. Early diagnosis requires both clinical suspicion and supporting radiological evidence. Early treatment results in reduced morbidity and mortality. This article reviews the imaging findings in opportunistic and endemic fungal infections.

Automatic scan triggering software "confused": Computed tomography angiography in foot arteriovenous malformation!

Multidetector computed tomography angiography (MDCTA) has become a well-established modality for limb angiography for a variety of indications. The technique of MDCTA depends on the scanner features including the number of detector rows, rotation speeds and single or dual source energy. Integral to a diagnostic quality CTA is the acquisition timing. Various techniques are available for determining the appropriate timing of scan acquisition which includes fixed delay, test bolus and the bolus tracking technique. The transit times of contrast from the aorta to the peripheral arteries shows a wide variability and is dependent upon the inter individual hemodynamic states. The bolus tracking technique is the most preferred one which allows reliable scan timing with acceptable contrast volume and radiation dose. Pitfalls with all these techniques are well described and we report one such technical pitfall in a case of left foot arteriovenous malformation (AVM) where the bolus tracking technique employed for scan triggering failed to initiate acquisition.

Early detection of differentiation syndrome by chest ultrasound in acute promyelocytic leukaemia

Differentiation syndrome (DS) in acute promyelocytic leukaemia (APML) is a life-threatening complication. The clinical features used to diagnose DS can be seen not only in APML patients with DS but also in APML patients with sepsis or heart failure(Larson & Tallman, 2003).Thus, the decision to treat DS with high dose dexamethasone based on clinical criteria alone can be erroneous. We investigated the role of chest ultrasonography in diagnosing DS in APML patients. Our hypothesis was based on the observation that pulmonary oedema, one of the earliest signs of DS, produces a mismatch in impedance between the fluid-filled interstitium and the air-filled alveoli. This mismatch in impedance leads to the comet tail sign on chest ultrasound (Lichtenstein et al, 1997). We postulated that a positive comet tail sign would be suggestive of DS in APML patients. In this single centre prospective study, all newly diagnosed APML patients underwent a daily chest ultrasound from day one until day 14 of therapy. The diagnosis of APML was made by bone marrow examination and demonstration of PML-RARA with real-time quantitative polymerase chain reaction (RQ-PCR). The patients were risk stratified as per Sanz criteria (Sanz et al, 2000). All patients were treated with the combination of arsenic trioxide (ATO) and All-trans retinoic acid (ATRA). ATO was given at the dose of 0 15 mg/ kg/day. ATRA was given at the dose of 25 mg/m body surface area for low risk APML and 45 mg/m for intermediateand high-risk cases as per institutional policy (Malhotra et al, 2010). Hydroxycarbamide was used to reduce leucocyte count when the total leucocyte count rose above 5 9 10/l. ATO and ATRA were continued until haematological recovery. A bone marrow examination and RQ-PCR PML-RARA were performed to document remission at end of induction therapy. DS was diagnosed when patient had at least three features of DS, in the absence of other causes– fever, weight gain of 5 kg, lung infiltrates, respiratory distress, pleural & pericardial effusion, hypotension and renal failure (Frankel et al, 1992). All patients receiving ATO/ATRA were started on DS prophylaxis with oral prednisolone (1 mg/kg/day).The patients who developed DS were treated with dexamethasone (10 mg twice daily). Point-of-care chest ultrasound was performed as per the International Consensus Conference on Lung ultrasound guidelines (Volpicelli et al, 2012), by the treating physician under the guidance of a qualified radiologist. Each hemithorax was divided into four quadrants – upper and lower anterior and upper and lower lateral quadrants divided transversely by the 2nd intercostal space. Ultrasound was done in all eight quadrants using a 1 0–5 0 MHz ultrasound probe. A comet-tail image was defined as a hyper-echogenic, coherent bundle with narrow basis arising from the pleural line and extending to the edge of the screen. Comet tail sign was positive if: (i) At least three comet tails per scan, (ii) diffusely positive with more than one positive scan per side and (iii) bilateral presence of comet tails (Volpicelli et al, 2012). Diagnostic accuracy of chest ultrasound was calculated using Chi-square test and Fishers exact test with P value <0 05 considered significant. Over an 18-month period, 35 cases of APML (median age, 30 years; 34 2% high-risk) were treated at our centre. There were five deaths (14 2%) during induction therapy. One death was secondary to cerebral haemorrhage while two deaths each were due to DS and sepsis. All deaths occurred within a week of initiating induction therapy. Overall, 8 5% of patients (n = 3) experienced DS by clinical criteria. Among them, one had the classical description of DS, occurring 3 days after initiation of therapy. The patient did not respond to DS therapy and succumbed to her illness on Day 5 of therapy. The other two patients had spontaneous onset of DS: one of these patients responded to therapy while the other succumbed to the illness on Day 2 of ATO/ATRA therapy. Chest ultrasound showed presence of comet tails in all 3 DS patients. The comet tail sign was detected 12 h prior to the onset of symptoms in the patient who developed DS after starting ATO/ATRA. The other 2 cases had presented with full blown DS and the comet tail sign was seen on examination by ultrasound at the time of initial presentation. Comet tail signs resolved by day 3 in the responding patient, but persisted in the second case of spontaneous DS until death on the second day of therapy. No comet tails were detected by chest ultrasound in the 30 patients who did not develop DS.A transient comet tail sign was detected for 2 days in two patients, and was attributed to fluid overload in a clinical setting of sepsis/acute kidney injury. The chest ultrasound had 100% sensitivity and 90 9% specificity in the detection of DS. [Fisher’s exact test (two tail): P = 0 0087]. Correspondence

HIV-infected children with hepatomegaly and ascites: is there something more than an infection?

1. Cattaneo D, Rizzardini G, Gervasoni C. Intolerance of dolutegravir-containing combination antiretroviral therapy: not just a pharmacokinetic drug interaction. AIDS 2017; 31:867–868. 2. Cattaneo D, Minisci D, Cozzi V, Riva A, Meraviglia P, Clementi E, et al. Dolutegravir plasma concentrations according to companion antiretroviral drug: unwanted drug interaction or desirable boosting effect? J Int AIDS Soc 2016; 19 (Suppl 7):216– 217(P303).