*Medical Student, ANU
At presentation, this case was a diagnostic and surgical dilemma. However, with the value of hindsight and clinical record review, the patient’s symptoms were readily explained.
A 78 year old male patient, with a history of 5-vessel coronary artery bypass in 2007, presented to a rural emergency department with right upper quadrant pain and a temperature of 38°C. The severe pain was constant, occurred suddenly, was radiating to the back and increasing on inspiration and recumbency. A week earlier the patient had an indwelling catheter inserted for urinary retention, and had presented four times in the following week complaining of haematuria with clots, diarrhoea and bloating. Investigations revealed moderately elevated liver enzymes (ALT 114, AST 109, GGT 113, ALKP 386), markedly elevated CRP (257) and reduced renal function (eGFR 85). The patient was an ex-smoker with a 30 pack year history, had a previous episode of deep vein thrombosis and a staphylococcal infection following a tibia fracture in 2001. He has a family history of pancreatic cancer and acquired renal disease.
Two days post presentation the patient became jaundiced, developed a soft ill-defined right upper quadrant mass and remained febrile. A chest x-ray reported a raised right hemi-diaphragm due to possible congenital eventration, previous surgery or subdiaphragmatic collection. Abdominal ultrasound revealed a normal appearing gallbladder and biliary system. Continued deterioration of the patient prompted a provisional diagnosis of acalculous cholecystitis (AAC), despite the ultrasound confirming a previous finding of a 16cm cyst containing a 2cm irregular calcification appearing to arise from the right kidney. Laparoscopic cholecystectomy was undertaken at the rural location.
Action based on the provisional diagnosis of AAC was reasonable considering its classically non-specific presentation (consisting of right upper quadrant pain, fever, leucocytosis and abnormal aminotransferases, alkaline phosphatase and bilirubin) and relatively poor outcome unless treated promptly. AAC is defined as acute inflammation and necrosis of the gall bladder in the absence of cholelithiasis1. It accounts for 10% of all acute cholecystitis and typically occurs in critically ill patients in relation to trauma, surgery, shock, burns, sepsis, prolonged fasting or total parenteral nutrition. Despite indistinguishable clinical signs, the mortality rate of AAC of 30% is significantly higher than calculous cholecystitis. In addition it is associated with severe complications of gangrene, perforation and empyema1. More recently AAC has been recognised to occur in a substantial number of outpatients, especially in males older than 65 years with risk factors including diabetes, vascular disease and hypertension1,2. In this population, which includes the patient under discussion, prompt cholecystectomy improves prognosis1,2. Hepatobiliary iminodiacetic acid (HIDA) scan is the gold standard diagnostic modality for AAC, but was unavailable in this rural location. The diagnostic criteria comprises inflammatory changes found on ultrasound or computerised tomography (CT) scan, however their variable sensitivity rendered the absence of radiological signs unhelpful in this case.
On laparoscopic exploration, the gallbladder and left liver lobe appeared normal, but the right liver lobe showed marked venous engorgement with bile-stained peritoneal fluid. Gross induration and inflammation of the right retroperitoneum sparked the decision to convert to laparotomy, which uncovered a football-sized potentially fragile cyst measuring 200×170mm in the upper pole of the right kidney, compromising venous drainage of the liver. At that stage it was unknown whether the cyst was neoplastic, parasitic or an infected simple cyst. Following interstate urology and radiology phone consultation from the operating theatre, an unplanned right nephrectomy was performed, with the cyst removed intact. The liver appearance vastly improved by the end of the procedure. Fortunately the patient made an uncomplicated recovery.
Review of the patient’s clinical records post-surgery revealed that investigations and urology review for painless haematuria and symptoms of bladder outlet obstruction six months prior to presentation had demonstrated a 280mm cyst in the upper pole of the right kidney. The cyst had enlarged and developed calcified nodularity compared to previous CT scans in 2007, but had remained unchanged since 2008 scans (Figure shown above).
Although urine cytology showed no evidence of malignant cells, cystic renal neoplasm could not be excluded. However, as the cyst was not thought to be the cause of his haematuria, the patient had only been treated for prostatic enlargement with tamsulosin. In addition, a cardiothoracic referral and investigations in 2008 also showed a lung mass, determined to be a hamartoma, despite growth and calcification on subsequent CT scan.
The renal cyst was found to be a large cystic papillary carcinoma of Fuhrman Grade 3, without lymph node, perinephric fat or vascular involvement. The unlikely possibility of metastasis could not be ruled out however, especially considering his known un-biopsied lung mass. The patient was referred to oncology for follow up.
Papillary carcinoma (15-20%) is the second most common type of renal cell carcinoma (RCC), after the clear cell variety (70%). It has a good prognosis with a five-year survival rate of 80-90%, probably because of their generally early stage at presentation3. Cystic changes occur in 4-15% of cases of RCC4. Radiological features of the cyst can aid diagnosis by pointing toward a benign or malignant cause. Benign features of a renal cyst on imaging include a thin wall, no septa, calcification or solid components; and no contrast enhancement. A proportion of cystic lesions are indeterminate as they may show marginally suspicious features; 40-60% of these turn out to be malignant cystic RCC5. Follow up of progression on CT usually indicates a neoplastic process.
In this case, growth on subsequent CT scans could have triggered biopsy or surgical resection. Percutaneous biopsy has been shown to have a lower risk of periotoneal seeding than previously thought and provides an accurate diagnosis5.
Clinical diagnosis of RCC is not necessarily straightforward as the ‘classic’ triad of haematuria, palpable renal mass and dull aching flank pain only occurs in 15% of cases6. It has also been observed that patients with cystic RCC are less likely to experience systemic symptoms of anorexia, weight loss and asthenia compared to patients with non-cystic RCC7. Though at the time they did not immediately appear to be linked, in hindsight this patient’s protracted presentation included all the classical features of renal carcinoma. Atypically, however, his abdominal pain appeared to originate in the right upper quadrant and radiate to the back rather than radiating from the flank to the abdomen, and the palpable mass was large enough to appear abdominal rather than retroperitoneal.
Several valuable lessons can be learned from this case. Not only is a thorough history from the patient important, but collateral history by following up previous records and imaging results is vital to making an accurate diagnosis and thus management plan. This is particularly crucial where invasive treatment such as surgery is required, to allow for necessary planning including transportation of the patient to the appropriate facility for diagnostic tests, the surgical procedure and postoperative care. Finally, it is helpful to reflect that while uncommon conditions such as acalculous cholecystitis do occur, common diseases are more likely and known local pathology is likely to be causing current symptoms.