Role of postoperative intact serum PTH as an early predictor of severe post-thyroidectomy hypocalcemia: a prospective study.

BACKGROUND: Post thyroidectomy hypocalcemia is a major sequel of thyroidectomy and continues to trouble the endocrinologists and the endocrine surgeons as there is no ideal predictive marker of hypocalcemia which has the potential to develop into a life-threatening complication. The role of early serum intact parathormone (iPTH) to predict post thyroidectomy hypocalcemia is becoming useful but the literature is still unclear regarding the optimal time of testing and the optimal cut-off value of serum iPTH. PATIENTS AND METHODS: This is a prospective cohort study of 111 patients who underwent total thyroidectomy in a tertiary care endocrine surgery referral unit. Serum iPTH was measured after 20 min and 4 h of surgery. Receiver-Operator characteristic Curve (ROC) was used to find out of the best cut-off value of S. iPTH 20 min and 4 h after surgery in predicting hypocalcemia. RESULTS: Hypocalcemia was noted in 60 (54%) out of 111 subjects who underwent total thyroidectomy. The best cut-off values of Serum iPTH to predict hypocalcemia was found to be 4.28 pmol/l at 20 min post total thyroidectomy with a sensitivity and specificity of 81.7% and 51%, respectively. In addition, patients with malignancy or central lymph nodal dissection were significantly over-represented in the hypocalcemia group with serum iPTH above the threshold level of 4.28 pmol/l. Below the cut off level, parenteral calcium supplementation was required in 23% (17/74) subjects while the rate was only 5.4% (2/37) patients when serum iPTH was above the cut-off level. CONCLUSIONS: The decline of serum iPTH below a specific level after surgery has predictive value together with other factors strictly related to patient, the thyroid disease itself and surgery. The risk of development of hypocalcemia and consequent need for calcium supplementation should be evaluated by clinical assessment along with serum PTH measurement.

Changing microbiological profile of pathogenic bacteria in diabetic foot infections: time for a rethink on which empirical therapy to choose?

AIMS/HYPOTHESIS: We studied the bacterial aetiology and antibiotic sensitivity pattern of diabetic foot ulcers in India. METHODS: Records of 447 hospitalised patients between 1991 and 2008 were retrospectively analysed between two time periods (before and after 1999) to compare bacterial aetiology and antimicrobial sensitivity patterns. The first three consecutive cultures from the same wound during treatment were evaluated. RESULTS: Of 1,632 cultures, 66% were polymicrobial, 23% monomicrobial and 11% sterile. In the monomicrobial group, 14% (n = 228) of cultures were Gram-negative, whereas 9% (n = 147) were Gram-positive. The most common pathogens in the first culture were Pseudomonas aeruginosa (20.1%), Staphylococcus aureus (17.2%) and Escherichia coli (16.3%). Results for the third cultures showed persistence of P. aeruginosa (15.3%) and E. coli (14.2%). Gram-negative isolates dominated over Gram-positive ones (25.3% vs 15.1%, p < 0.05). Antibiotic sensitivity patterns before and after 1999 were: piperacillin-tazobactam 74% vs 66% (p < 0.005), imipenem 77% vs 85% (NS), cefoperazone-sulbactam 47% vs 44% (p < 0.005), amikacin 62% vs 78% (NS), ceftriaxone 41% vs 36% (p < 0.005), amoxicillin-clavulanate 51% vs 43% (p < 0.05) and clindamycin 43% vs 36% (p < 0.005), respectively. CONCLUSIONS/INTERPRETATION: Unlike in the West, in India Gram-negative bacteria were found to have always been dominant in the wounds of patients with diabetic foot infections. Infection with polymicrobial multidrug-resistant Gram-negative bacilli is common. The policy of empirical antimicrobial therapy at tertiary care needs to be changed.