Final answer:
Diagnosis coding for the patient with epigastric pain, a history of depression, and H. pylori gastritis is K29.71, F32.9, Z72.89, denoting gastritis due to H. pylori, unspecified depression, and issues related to lifestyle, such as social drinking.
Step-by-step explanation:
The patient's diagnosis coding for this case, considering the clinical presentation and the findings from an esophagogastroduodenoscopy (EGD), is K29.71, F32.9, and Z72.89. The patient presented with epigastric pain, a history of depression, vomiting dark blood, denial of NSAID or alcohol abuse, and was diagnosed with moderate active chronic gastritis with H. pylori infection.
The International Classification of Diseases (ICD) codes for this scenario represent gastritis due to H. pylori (K29.71), unspecified depression (F32.9), and other problems related to lifestyle (Z72.89) due to social drinking. The evidence of active gastritis is consistent with the ICD code K29.71, the patient's ongoing citalopram treatment suggests depression for which the F32.9 code is used, and the recent significant alcohol consumption is captured by Z72.89.